diff --git a/container/gmap/gmap_hash_any_any_map.go b/container/gmap/gmap_hash_any_any_map.go
index f6abe77d7..e51da00d1 100644
--- a/container/gmap/gmap_hash_any_any_map.go
+++ b/container/gmap/gmap_hash_any_any_map.go
@@ -265,25 +265,25 @@ func (m *AnyAnyMap) GetOrSetFuncLock(key interface{}, f func() interface{}) inte
 
 // GetVar returns a Var with the value by given <key>.
 // The returned Var is un-concurrent safe.
-func (m *AnyAnyMap) GetVar(key interface{}) *gvar.Var {
+func (m *AnyAnyMap) GetVar(key interface{}) gvar.Var {
 	return gvar.New(m.Get(key))
 }
 
 // GetVarOrSet returns a Var with result from GetVarOrSet.
 // The returned Var is un-concurrent safe.
-func (m *AnyAnyMap) GetVarOrSet(key interface{}, value interface{}) *gvar.Var {
+func (m *AnyAnyMap) GetVarOrSet(key interface{}, value interface{}) gvar.Var {
 	return gvar.New(m.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a Var with result from GetOrSetFunc.
 // The returned Var is un-concurrent safe.
-func (m *AnyAnyMap) GetVarOrSetFunc(key interface{}, f func() interface{}) *gvar.Var {
+func (m *AnyAnyMap) GetVarOrSetFunc(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a Var with result from GetOrSetFuncLock.
 // The returned Var is un-concurrent safe.
-func (m *AnyAnyMap) GetVarOrSetFuncLock(key interface{}, f func() interface{}) *gvar.Var {
+func (m *AnyAnyMap) GetVarOrSetFuncLock(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gmap/gmap_hash_int_any_map.go b/container/gmap/gmap_hash_int_any_map.go
index a4a155770..4b4b93520 100644
--- a/container/gmap/gmap_hash_int_any_map.go
+++ b/container/gmap/gmap_hash_int_any_map.go
@@ -263,25 +263,25 @@ func (m *IntAnyMap) GetOrSetFuncLock(key int, f func() interface{}) interface{}
 
 // GetVar returns a Var with the value by given <key>.
 // The returned Var is un-concurrent safe.
-func (m *IntAnyMap) GetVar(key int) *gvar.Var {
+func (m *IntAnyMap) GetVar(key int) gvar.Var {
 	return gvar.New(m.Get(key))
 }
 
 // GetVarOrSet returns a Var with result from GetVarOrSet.
 // The returned Var is un-concurrent safe.
-func (m *IntAnyMap) GetVarOrSet(key int, value interface{}) *gvar.Var {
+func (m *IntAnyMap) GetVarOrSet(key int, value interface{}) gvar.Var {
 	return gvar.New(m.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a Var with result from GetOrSetFunc.
 // The returned Var is un-concurrent safe.
-func (m *IntAnyMap) GetVarOrSetFunc(key int, f func() interface{}) *gvar.Var {
+func (m *IntAnyMap) GetVarOrSetFunc(key int, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a Var with result from GetOrSetFuncLock.
 // The returned Var is un-concurrent safe.
-func (m *IntAnyMap) GetVarOrSetFuncLock(key int, f func() interface{}) *gvar.Var {
+func (m *IntAnyMap) GetVarOrSetFuncLock(key int, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gmap/gmap_hash_str_any_map.go b/container/gmap/gmap_hash_str_any_map.go
index 906537809..b5cd53ba1 100644
--- a/container/gmap/gmap_hash_str_any_map.go
+++ b/container/gmap/gmap_hash_str_any_map.go
@@ -259,25 +259,25 @@ func (m *StrAnyMap) GetOrSetFuncLock(key string, f func() interface{}) interface
 
 // GetVar returns a Var with the value by given <key>.
 // The returned Var is un-concurrent safe.
-func (m *StrAnyMap) GetVar(key string) *gvar.Var {
+func (m *StrAnyMap) GetVar(key string) gvar.Var {
 	return gvar.New(m.Get(key))
 }
 
 // GetVarOrSet returns a Var with result from GetVarOrSet.
 // The returned Var is un-concurrent safe.
-func (m *StrAnyMap) GetVarOrSet(key string, value interface{}) *gvar.Var {
+func (m *StrAnyMap) GetVarOrSet(key string, value interface{}) gvar.Var {
 	return gvar.New(m.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a Var with result from GetOrSetFunc.
 // The returned Var is un-concurrent safe.
-func (m *StrAnyMap) GetVarOrSetFunc(key string, f func() interface{}) *gvar.Var {
+func (m *StrAnyMap) GetVarOrSetFunc(key string, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a Var with result from GetOrSetFuncLock.
 // The returned Var is un-concurrent safe.
-func (m *StrAnyMap) GetVarOrSetFuncLock(key string, f func() interface{}) *gvar.Var {
+func (m *StrAnyMap) GetVarOrSetFuncLock(key string, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gmap/gmap_list_map.go b/container/gmap/gmap_list_map.go
index 9a6e97ae2..0e6f5f6de 100644
--- a/container/gmap/gmap_list_map.go
+++ b/container/gmap/gmap_list_map.go
@@ -332,25 +332,25 @@ func (m *ListMap) GetOrSetFuncLock(key interface{}, f func() interface{}) interf
 
 // GetVar returns a Var with the value by given <key>.
 // The returned Var is un-concurrent safe.
-func (m *ListMap) GetVar(key interface{}) *gvar.Var {
+func (m *ListMap) GetVar(key interface{}) gvar.Var {
 	return gvar.New(m.Get(key))
 }
 
 // GetVarOrSet returns a Var with result from GetVarOrSet.
 // The returned Var is un-concurrent safe.
-func (m *ListMap) GetVarOrSet(key interface{}, value interface{}) *gvar.Var {
+func (m *ListMap) GetVarOrSet(key interface{}, value interface{}) gvar.Var {
 	return gvar.New(m.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a Var with result from GetOrSetFunc.
 // The returned Var is un-concurrent safe.
-func (m *ListMap) GetVarOrSetFunc(key interface{}, f func() interface{}) *gvar.Var {
+func (m *ListMap) GetVarOrSetFunc(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a Var with result from GetOrSetFuncLock.
 // The returned Var is un-concurrent safe.
-func (m *ListMap) GetVarOrSetFuncLock(key interface{}, f func() interface{}) *gvar.Var {
+func (m *ListMap) GetVarOrSetFuncLock(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(m.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gtree/gtree_avltree.go b/container/gtree/gtree_avltree.go
index aa195aa1c..48b0efb2f 100644
--- a/container/gtree/gtree_avltree.go
+++ b/container/gtree/gtree_avltree.go
@@ -173,25 +173,25 @@ func (tree *AVLTree) GetOrSetFuncLock(key interface{}, f func() interface{}) int
 
 // GetVar returns a gvar.Var with the value by given <key>.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *AVLTree) GetVar(key interface{}) *gvar.Var {
+func (tree *AVLTree) GetVar(key interface{}) gvar.Var {
 	return gvar.New(tree.Get(key))
 }
 
 // GetVarOrSet returns a gvar.Var with result from GetVarOrSet.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *AVLTree) GetVarOrSet(key interface{}, value interface{}) *gvar.Var {
+func (tree *AVLTree) GetVarOrSet(key interface{}, value interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a gvar.Var with result from GetOrSetFunc.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *AVLTree) GetVarOrSetFunc(key interface{}, f func() interface{}) *gvar.Var {
+func (tree *AVLTree) GetVarOrSetFunc(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a gvar.Var with result from GetOrSetFuncLock.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *AVLTree) GetVarOrSetFuncLock(key interface{}, f func() interface{}) *gvar.Var {
+func (tree *AVLTree) GetVarOrSetFuncLock(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gtree/gtree_btree.go b/container/gtree/gtree_btree.go
index 05c567591..33e4e219b 100644
--- a/container/gtree/gtree_btree.go
+++ b/container/gtree/gtree_btree.go
@@ -171,25 +171,25 @@ func (tree *BTree) GetOrSetFuncLock(key interface{}, f func() interface{}) inter
 
 // GetVar returns a gvar.Var with the value by given <key>.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *BTree) GetVar(key interface{}) *gvar.Var {
+func (tree *BTree) GetVar(key interface{}) gvar.Var {
 	return gvar.New(tree.Get(key))
 }
 
 // GetVarOrSet returns a gvar.Var with result from GetVarOrSet.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *BTree) GetVarOrSet(key interface{}, value interface{}) *gvar.Var {
+func (tree *BTree) GetVarOrSet(key interface{}, value interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a gvar.Var with result from GetOrSetFunc.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *BTree) GetVarOrSetFunc(key interface{}, f func() interface{}) *gvar.Var {
+func (tree *BTree) GetVarOrSetFunc(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a gvar.Var with result from GetOrSetFuncLock.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *BTree) GetVarOrSetFuncLock(key interface{}, f func() interface{}) *gvar.Var {
+func (tree *BTree) GetVarOrSetFuncLock(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gtree/gtree_redblacktree.go b/container/gtree/gtree_redblacktree.go
index f23d7838d..343d05221 100644
--- a/container/gtree/gtree_redblacktree.go
+++ b/container/gtree/gtree_redblacktree.go
@@ -213,25 +213,25 @@ func (tree *RedBlackTree) GetOrSetFuncLock(key interface{}, f func() interface{}
 
 // GetVar returns a gvar.Var with the value by given <key>.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *RedBlackTree) GetVar(key interface{}) *gvar.Var {
+func (tree *RedBlackTree) GetVar(key interface{}) gvar.Var {
 	return gvar.New(tree.Get(key))
 }
 
 // GetVarOrSet returns a gvar.Var with result from GetVarOrSet.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *RedBlackTree) GetVarOrSet(key interface{}, value interface{}) *gvar.Var {
+func (tree *RedBlackTree) GetVarOrSet(key interface{}, value interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSet(key, value))
 }
 
 // GetVarOrSetFunc returns a gvar.Var with result from GetOrSetFunc.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *RedBlackTree) GetVarOrSetFunc(key interface{}, f func() interface{}) *gvar.Var {
+func (tree *RedBlackTree) GetVarOrSetFunc(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSetFunc(key, f))
 }
 
 // GetVarOrSetFuncLock returns a gvar.Var with result from GetOrSetFuncLock.
 // The returned gvar.Var is un-concurrent safe.
-func (tree *RedBlackTree) GetVarOrSetFuncLock(key interface{}, f func() interface{}) *gvar.Var {
+func (tree *RedBlackTree) GetVarOrSetFuncLock(key interface{}, f func() interface{}) gvar.Var {
 	return gvar.New(tree.GetOrSetFuncLock(key, f))
 }
 
diff --git a/container/gvar/gvar.go b/container/gvar/gvar.go
index c573a5b32..0059bd251 100644
--- a/container/gvar/gvar.go
+++ b/container/gvar/gvar.go
@@ -8,251 +8,75 @@
 package gvar
 
 import (
-	"encoding/json"
-	"time"
-
-	"github.com/gogf/gf/internal/empty"
-
-	"github.com/gogf/gf/container/gtype"
+	"github.com/gogf/gf/internal/intstore"
 	"github.com/gogf/gf/os/gtime"
-	"github.com/gogf/gf/util/gconv"
+	"reflect"
+	"time"
 )
 
-// Var is an universal variable type.
-type Var struct {
-	value interface{} // Underlying value.
-	safe  bool        // Concurrent safe or not.
+// Var is a universal variable interface, like generics.
+type Var interface {
+	IsEmpty() bool
+	IsNil() bool
+
+	Val() interface{}
+	Set(value interface{}) (old interface{})
+	Interface() interface{}
+	String() string
+
+	Bool() bool
+
+	Int() int
+	Int16() int16
+	Int32() int32
+	Int64() int64
+	Int8() int8
+
+	Uint() uint
+	Uint16() uint16
+	Uint32() uint32
+	Uint64() uint64
+	Uint8() uint8
+
+	Float32() float32
+	Float64() float64
+
+	Ints() []int
+	Uints() []uint
+	Vars() []Var
+	Bytes() []byte
+	Floats() []float64
+	Array() []interface{}
+	Slice() []interface{}
+	Strings() []string
+	Interfaces() []interface{}
+
+	Map(tags ...string) map[string]interface{}
+	MapDeep(tags ...string) map[string]interface{}
+	MapStrStr(tags ...string) map[string]string
+	MapStrStrDeep(tags ...string) map[string]string
+	MapStrVar(tags ...string) map[string]Var
+	MapStrVarDeep(tags ...string) map[string]Var
+	MapToMap(pointer interface{}, mapping ...map[string]string) (err error)
+	MapToMapDeep(pointer interface{}, mapping ...map[string]string) (err error)
+	MapToMaps(pointer interface{}, mapping ...map[string]string) (err error)
+	MapToMapsDeep(pointer interface{}, mapping ...map[string]string) (err error)
+
+	Struct(pointer interface{}, mapping ...map[string]string) error
+	StructDeep(pointer interface{}, mapping ...map[string]string) error
+	Structs(pointer interface{}, mapping ...map[string]string) (err error)
+	StructsDeep(pointer interface{}, mapping ...map[string]string) (err error)
+
+	Time(format ...string) time.Time
+	Duration() time.Duration
+	GTime(format ...string) *gtime.Time
+
+	MarshalJSON() ([]byte, error)
+	UnmarshalJSON(b []byte) error
+	UnmarshalValue(value interface{}) error
 }
 
-// New creates and returns a new *Var with given <value>.
-// The optional parameter <safe> specifies whether Var is used in concurrent-safety,
-// which is false in default.
-func New(value interface{}, safe ...bool) *Var {
-	v := Create(value, safe...)
-	return &v
-}
-
-// Create creates and returns a new Var with given <value>.
-// The optional parameter <safe> specifies whether Var is used in concurrent-safety,
-// which is false in default.
-func Create(value interface{}, safe ...bool) Var {
-	v := Var{}
-	if len(safe) > 0 && !safe[0] {
-		v.safe = true
-		v.value = gtype.NewInterface(value)
-	} else {
-		v.value = value
-	}
-	return v
-}
-
-// Clone does a shallow copy of current Var and returns a pointer to this Var.
-func (v *Var) Clone() *Var {
-	return New(v.Val(), v.safe)
-}
-
-// Set sets <value> to <v>, and returns the old value.
-func (v *Var) Set(value interface{}) (old interface{}) {
-	if v.safe {
-		if t, ok := v.value.(*gtype.Interface); ok {
-			old = t.Set(value)
-			return
-		}
-	}
-	old = v.value
-	v.value = value
-	return
-}
-
-// Val returns the current value of <v>.
-func (v *Var) Val() interface{} {
-	if v == nil {
-		return nil
-	}
-	if v.safe {
-		if t, ok := v.value.(*gtype.Interface); ok {
-			return t.Val()
-		}
-	}
-	return v.value
-}
-
-// Interface is alias of Val.
-func (v *Var) Interface() interface{} {
-	return v.Val()
-}
-
-// IsNil checks whether <v> is nil.
-func (v *Var) IsNil() bool {
-	return v.Val() == nil
-}
-
-// IsEmpty checks whether <v> is empty.
-func (v *Var) IsEmpty() bool {
-	return empty.IsEmpty(v.Val())
-}
-
-// Bytes converts and returns <v> as []byte.
-func (v *Var) Bytes() []byte {
-	return gconv.Bytes(v.Val())
-}
-
-// String converts and returns <v> as string.
-func (v *Var) String() string {
-	return gconv.String(v.Val())
-}
-
-// Bool converts and returns <v> as bool.
-func (v *Var) Bool() bool {
-	return gconv.Bool(v.Val())
-}
-
-// Int converts and returns <v> as int.
-func (v *Var) Int() int {
-	return gconv.Int(v.Val())
-}
-
-// Ints converts and returns <v> as []int.
-func (v *Var) Ints() []int {
-	return gconv.Ints(v.Val())
-}
-
-// Int8 converts and returns <v> as int8.
-func (v *Var) Int8() int8 {
-	return gconv.Int8(v.Val())
-}
-
-// Int16 converts and returns <v> as int16.
-func (v *Var) Int16() int16 {
-	return gconv.Int16(v.Val())
-}
-
-// Int32 converts and returns <v> as int32.
-func (v *Var) Int32() int32 {
-	return gconv.Int32(v.Val())
-}
-
-// Int64 converts and returns <v> as int64.
-func (v *Var) Int64() int64 {
-	return gconv.Int64(v.Val())
-}
-
-// Uint converts and returns <v> as uint.
-func (v *Var) Uint() uint {
-	return gconv.Uint(v.Val())
-}
-
-// Uints converts and returns <v> as []uint.
-func (v *Var) Uints() []uint {
-	return gconv.Uints(v.Val())
-}
-
-// Uint8 converts and returns <v> as uint8.
-func (v *Var) Uint8() uint8 {
-	return gconv.Uint8(v.Val())
-}
-
-// Uint16 converts and returns <v> as uint16.
-func (v *Var) Uint16() uint16 {
-	return gconv.Uint16(v.Val())
-}
-
-// Uint32 converts and returns <v> as uint32.
-func (v *Var) Uint32() uint32 {
-	return gconv.Uint32(v.Val())
-}
-
-// Uint64 converts and returns <v> as uint64.
-func (v *Var) Uint64() uint64 {
-	return gconv.Uint64(v.Val())
-}
-
-// Float32 converts and returns <v> as float32.
-func (v *Var) Float32() float32 {
-	return gconv.Float32(v.Val())
-}
-
-// Float64 converts and returns <v> as float64.
-func (v *Var) Float64() float64 {
-	return gconv.Float64(v.Val())
-}
-
-// Floats converts and returns <v> as []float64.
-func (v *Var) Floats() []float64 {
-	return gconv.Floats(v.Val())
-}
-
-// Strings converts and returns <v> as []string.
-func (v *Var) Strings() []string {
-	return gconv.Strings(v.Val())
-}
-
-// Interfaces converts and returns <v> as []interfaces{}.
-func (v *Var) Interfaces() []interface{} {
-	return gconv.Interfaces(v.Val())
-}
-
-// Slice is alias of Interfaces.
-func (v *Var) Slice() []interface{} {
-	return v.Interfaces()
-}
-
-// Array is alias of Interfaces.
-func (v *Var) Array() []interface{} {
-	return v.Interfaces()
-}
-
-// Vars converts and returns <v> as []*Var.
-func (v *Var) Vars() []*Var {
-	array := gconv.Interfaces(v.Val())
-	if len(array) == 0 {
-		return nil
-	}
-	vars := make([]*Var, len(array))
-	for k, v := range array {
-		vars[k] = New(v)
-	}
-	return vars
-}
-
-// Time converts and returns <v> as time.Time.
-// The parameter <format> specifies the format of the time string using gtime,
-// eg: Y-m-d H:i:s.
-func (v *Var) Time(format ...string) time.Time {
-	return gconv.Time(v.Val(), format...)
-}
-
-// Duration converts and returns <v> as time.Duration.
-// If value of <v> is string, then it uses time.ParseDuration for conversion.
-func (v *Var) Duration() time.Duration {
-	return gconv.Duration(v.Val())
-}
-
-// GTime converts and returns <v> as *gtime.Time.
-// The parameter <format> specifies the format of the time string using gtime,
-// eg: Y-m-d H:i:s.
-func (v *Var) GTime(format ...string) *gtime.Time {
-	return gconv.GTime(v.Val(), format...)
-}
-
-// MarshalJSON implements the interface MarshalJSON for json.Marshal.
-func (v *Var) MarshalJSON() ([]byte, error) {
-	return json.Marshal(v.Val())
-}
-
-// UnmarshalJSON implements the interface UnmarshalJSON for json.Unmarshal.
-func (v *Var) UnmarshalJSON(b []byte) error {
-	var i interface{}
-	err := json.Unmarshal(b, &i)
-	if err != nil {
-		return err
-	}
-	v.Set(i)
-	return nil
-}
-
-// UnmarshalValue is an interface implement which sets any type of value for Var.
-func (v *Var) UnmarshalValue(value interface{}) error {
-	v.Set(value)
-	return nil
+func init() {
+	// Register the type of gvar.VarImp to local variable.
+	intstore.ReflectTypeVarImp = reflect.TypeOf(VarImp{})
 }
diff --git a/container/gvar/gvar_imp.go b/container/gvar/gvar_imp.go
new file mode 100644
index 000000000..31783de39
--- /dev/null
+++ b/container/gvar/gvar_imp.go
@@ -0,0 +1,264 @@
+// Copyright 2018-2019 gf Author(https://github.com/gogf/gf). All Rights Reserved.
+//
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT was not distributed with this file,
+// You can obtain one at https://github.com/gogf/gf.
+
+package gvar
+
+import (
+	"encoding/json"
+	"time"
+
+	"github.com/gogf/gf/internal/empty"
+
+	"github.com/gogf/gf/container/gtype"
+	"github.com/gogf/gf/os/gtime"
+	"github.com/gogf/gf/util/gconv"
+)
+
+// VarImp is an universal variable type implementer.
+type VarImp struct {
+	value interface{} // Underlying value.
+	safe  bool        // Concurrent safe or not.
+}
+
+// New creates and returns a new Var with given <value>.
+// The optional parameter <safe> specifies whether Var is used in concurrent-safety,
+// which is false in default.
+func New(value interface{}, safe ...bool) Var {
+	v := VarImp{}
+	if len(safe) > 0 && !safe[0] {
+		v.safe = true
+		v.value = gtype.NewInterface(value)
+	} else {
+		v.value = value
+	}
+	return &v
+}
+
+// Create creates and returns a new VarImp with given <value>.
+// The optional parameter <safe> specifies whether Var is used in concurrent-safety,
+// which is false in default.
+// Deprecated.
+func Create(value interface{}, safe ...bool) VarImp {
+	v := VarImp{}
+	if len(safe) > 0 && !safe[0] {
+		v.safe = true
+		v.value = gtype.NewInterface(value)
+	} else {
+		v.value = value
+	}
+	return v
+}
+
+// Clone does a shallow copy of current Var and returns a pointer to this Var.
+func (v *VarImp) Clone() Var {
+	return New(v.Val(), v.safe)
+}
+
+// Set sets <value> to <v>, and returns the old value.
+func (v *VarImp) Set(value interface{}) (old interface{}) {
+	if v.safe {
+		if t, ok := v.value.(*gtype.Interface); ok {
+			old = t.Set(value)
+			return
+		}
+	}
+	old = v.value
+	v.value = value
+	return
+}
+
+// Val returns the current value of <v>.
+func (v *VarImp) Val() interface{} {
+	if v == nil {
+		return nil
+	}
+	if v.safe {
+		if t, ok := v.value.(*gtype.Interface); ok {
+			return t.Val()
+		}
+	}
+	return v.value
+}
+
+// Interface is alias of Val.
+func (v *VarImp) Interface() interface{} {
+	return v.Val()
+}
+
+// IsNil checks whether <v> is nil.
+func (v *VarImp) IsNil() bool {
+	return v.Val() == nil
+}
+
+// IsEmpty checks whether <v> is empty.
+func (v *VarImp) IsEmpty() bool {
+	return empty.IsEmpty(v.Val())
+}
+
+// Bytes converts and returns <v> as []byte.
+func (v *VarImp) Bytes() []byte {
+	return gconv.Bytes(v.Val())
+}
+
+// String converts and returns <v> as string.
+func (v *VarImp) String() string {
+	return gconv.String(v.Val())
+}
+
+// Bool converts and returns <v> as bool.
+func (v *VarImp) Bool() bool {
+	return gconv.Bool(v.Val())
+}
+
+// Int converts and returns <v> as int.
+func (v *VarImp) Int() int {
+	return gconv.Int(v.Val())
+}
+
+// Ints converts and returns <v> as []int.
+func (v *VarImp) Ints() []int {
+	return gconv.Ints(v.Val())
+}
+
+// Int8 converts and returns <v> as int8.
+func (v *VarImp) Int8() int8 {
+	return gconv.Int8(v.Val())
+}
+
+// Int16 converts and returns <v> as int16.
+func (v *VarImp) Int16() int16 {
+	return gconv.Int16(v.Val())
+}
+
+// Int32 converts and returns <v> as int32.
+func (v *VarImp) Int32() int32 {
+	return gconv.Int32(v.Val())
+}
+
+// Int64 converts and returns <v> as int64.
+func (v *VarImp) Int64() int64 {
+	return gconv.Int64(v.Val())
+}
+
+// Uint converts and returns <v> as uint.
+func (v *VarImp) Uint() uint {
+	return gconv.Uint(v.Val())
+}
+
+// Uints converts and returns <v> as []uint.
+func (v *VarImp) Uints() []uint {
+	return gconv.Uints(v.Val())
+}
+
+// Uint8 converts and returns <v> as uint8.
+func (v *VarImp) Uint8() uint8 {
+	return gconv.Uint8(v.Val())
+}
+
+// Uint16 converts and returns <v> as uint16.
+func (v *VarImp) Uint16() uint16 {
+	return gconv.Uint16(v.Val())
+}
+
+// Uint32 converts and returns <v> as uint32.
+func (v *VarImp) Uint32() uint32 {
+	return gconv.Uint32(v.Val())
+}
+
+// Uint64 converts and returns <v> as uint64.
+func (v *VarImp) Uint64() uint64 {
+	return gconv.Uint64(v.Val())
+}
+
+// Float32 converts and returns <v> as float32.
+func (v *VarImp) Float32() float32 {
+	return gconv.Float32(v.Val())
+}
+
+// Float64 converts and returns <v> as float64.
+func (v *VarImp) Float64() float64 {
+	return gconv.Float64(v.Val())
+}
+
+// Floats converts and returns <v> as []float64.
+func (v *VarImp) Floats() []float64 {
+	return gconv.Floats(v.Val())
+}
+
+// Strings converts and returns <v> as []string.
+func (v *VarImp) Strings() []string {
+	return gconv.Strings(v.Val())
+}
+
+// Interfaces converts and returns <v> as []interfaces{}.
+func (v *VarImp) Interfaces() []interface{} {
+	return gconv.Interfaces(v.Val())
+}
+
+// Slice is alias of Interfaces.
+func (v *VarImp) Slice() []interface{} {
+	return v.Interfaces()
+}
+
+// Array is alias of Interfaces.
+func (v *VarImp) Array() []interface{} {
+	return v.Interfaces()
+}
+
+// Vars converts and returns <v> as []Var.
+func (v *VarImp) Vars() []Var {
+	array := gconv.Interfaces(v.Val())
+	if len(array) == 0 {
+		return nil
+	}
+	vars := make([]Var, len(array))
+	for k, v := range array {
+		vars[k] = New(v)
+	}
+	return vars
+}
+
+// Time converts and returns <v> as time.Time.
+// The parameter <format> specifies the format of the time string using gtime,
+// eg: Y-m-d H:i:s.
+func (v *VarImp) Time(format ...string) time.Time {
+	return gconv.Time(v.Val(), format...)
+}
+
+// Duration converts and returns <v> as time.Duration.
+// If value of <v> is string, then it uses time.ParseDuration for conversion.
+func (v *VarImp) Duration() time.Duration {
+	return gconv.Duration(v.Val())
+}
+
+// GTime converts and returns <v> as *gtime.Time.
+// The parameter <format> specifies the format of the time string using gtime,
+// eg: Y-m-d H:i:s.
+func (v *VarImp) GTime(format ...string) *gtime.Time {
+	return gconv.GTime(v.Val(), format...)
+}
+
+// MarshalJSON implements the interface MarshalJSON for json.Marshal.
+func (v *VarImp) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.Val())
+}
+
+// UnmarshalJSON implements the interface UnmarshalJSON for json.Unmarshal.
+func (v *VarImp) UnmarshalJSON(b []byte) error {
+	var i interface{}
+	err := json.Unmarshal(b, &i)
+	if err != nil {
+		return err
+	}
+	v.Set(i)
+	return nil
+}
+
+// UnmarshalValue is an interface implement which sets any type of value for Var.
+func (v *VarImp) UnmarshalValue(value interface{}) error {
+	v.Set(value)
+	return nil
+}
diff --git a/container/gvar/gvar_map.go b/container/gvar/gvar_imp_map.go
similarity index 60%
rename from container/gvar/gvar_map.go
rename to container/gvar/gvar_imp_map.go
index ba6156f3f..c9ed6cc67 100644
--- a/container/gvar/gvar_map.go
+++ b/container/gvar/gvar_imp_map.go
@@ -9,20 +9,20 @@ package gvar
 import "github.com/gogf/gf/util/gconv"
 
 // Map converts and returns <v> as map[string]interface{}.
-func (v *Var) Map(tags ...string) map[string]interface{} {
+func (v *VarImp) Map(tags ...string) map[string]interface{} {
 	return gconv.Map(v.Val(), tags...)
 }
 
 // MapStrStr converts and returns <v> as map[string]string.
-func (v *Var) MapStrStr(tags ...string) map[string]string {
+func (v *VarImp) MapStrStr(tags ...string) map[string]string {
 	return gconv.MapStrStr(v.Val(), tags...)
 }
 
-// MapStrVar converts and returns <v> as map[string]*Var.
-func (v *Var) MapStrVar(tags ...string) map[string]*Var {
+// MapStrVar converts and returns <v> as map[string]Var.
+func (v *VarImp) MapStrVar(tags ...string) map[string]Var {
 	m := v.Map(tags...)
 	if len(m) > 0 {
-		vMap := make(map[string]*Var, len(m))
+		vMap := make(map[string]Var, len(m))
 		for k, v := range m {
 			vMap[k] = New(v)
 		}
@@ -32,20 +32,20 @@ func (v *Var) MapStrVar(tags ...string) map[string]*Var {
 }
 
 // MapDeep converts and returns <v> as map[string]interface{} recursively.
-func (v *Var) MapDeep(tags ...string) map[string]interface{} {
+func (v *VarImp) MapDeep(tags ...string) map[string]interface{} {
 	return gconv.MapDeep(v.Val(), tags...)
 }
 
 // MapDeep converts and returns <v> as map[string]string recursively.
-func (v *Var) MapStrStrDeep(tags ...string) map[string]string {
+func (v *VarImp) MapStrStrDeep(tags ...string) map[string]string {
 	return gconv.MapStrStrDeep(v.Val(), tags...)
 }
 
-// MapStrVarDeep converts and returns <v> as map[string]*Var recursively.
-func (v *Var) MapStrVarDeep(tags ...string) map[string]*Var {
+// MapStrVarDeep converts and returns <v> as map[string]*VarImp recursively.
+func (v *VarImp) MapStrVarDeep(tags ...string) map[string]Var {
 	m := v.MapDeep(tags...)
 	if len(m) > 0 {
-		vMap := make(map[string]*Var, len(m))
+		vMap := make(map[string]Var, len(m))
 		for k, v := range m {
 			vMap[k] = New(v)
 		}
@@ -56,32 +56,32 @@ func (v *Var) MapStrVarDeep(tags ...string) map[string]*Var {
 
 // Maps converts and returns <v> as map[string]string.
 // See gconv.Maps.
-func (v *Var) Maps(tags ...string) []map[string]interface{} {
+func (v *VarImp) Maps(tags ...string) []map[string]interface{} {
 	return gconv.Maps(v.Val(), tags...)
 }
 
 // MapToMap converts any map type variable <params> to another map type variable <pointer>.
 // See gconv.MapToMap.
-func (v *Var) MapToMap(pointer interface{}) (err error) {
-	return gconv.MapToMap(v.Val(), pointer)
+func (v *VarImp) MapToMap(pointer interface{}, mapping ...map[string]string) (err error) {
+	return gconv.MapToMap(v.Val(), pointer, mapping...)
 }
 
 // MapToMapDeep converts any map type variable <params> to another map type variable
 // <pointer> recursively.
 // See gconv.MapToMapDeep.
-func (v *Var) MapToMapDeep(pointer interface{}) (err error) {
-	return gconv.MapToMapDeep(v.Val(), pointer)
+func (v *VarImp) MapToMapDeep(pointer interface{}, mapping ...map[string]string) (err error) {
+	return gconv.MapToMapDeep(v.Val(), pointer, mapping...)
 }
 
 // MapToMaps converts any map type variable <params> to another map type variable <pointer>.
 // See gconv.MapToMaps.
-func (v *Var) MapToMaps(pointer interface{}, mapping ...map[string]string) (err error) {
+func (v *VarImp) MapToMaps(pointer interface{}, mapping ...map[string]string) (err error) {
 	return gconv.MapToMaps(v.Val(), pointer, mapping...)
 }
 
 // MapToMapsDeep converts any map type variable <params> to another map type variable
 // <pointer> recursively.
 // See gconv.MapToMapsDeep.
-func (v *Var) MapToMapsDeep(pointer interface{}, mapping ...map[string]string) (err error) {
+func (v *VarImp) MapToMapsDeep(pointer interface{}, mapping ...map[string]string) (err error) {
 	return gconv.MapToMapsDeep(v.Val(), pointer, mapping...)
 }
diff --git a/container/gvar/gvar_struct.go b/container/gvar/gvar_imp_struct.go
similarity index 80%
rename from container/gvar/gvar_struct.go
rename to container/gvar/gvar_imp_struct.go
index 6ae985279..8afc9e3f1 100644
--- a/container/gvar/gvar_struct.go
+++ b/container/gvar/gvar_imp_struct.go
@@ -13,24 +13,24 @@ import (
 // Struct maps value of <v> to <pointer>.
 // The parameter <pointer> should be a pointer to a struct instance.
 // The parameter <mapping> is used to specify the key-to-attribute mapping rules.
-func (v *Var) Struct(pointer interface{}, mapping ...map[string]string) error {
+func (v *VarImp) Struct(pointer interface{}, mapping ...map[string]string) error {
 	return gconv.Struct(v.Val(), pointer, mapping...)
 }
 
 // Struct maps value of <v> to <pointer> recursively.
 // The parameter <pointer> should be a pointer to a struct instance.
 // The parameter <mapping> is used to specify the key-to-attribute mapping rules.
-func (v *Var) StructDeep(pointer interface{}, mapping ...map[string]string) error {
+func (v *VarImp) StructDeep(pointer interface{}, mapping ...map[string]string) error {
 	return gconv.StructDeep(v.Val(), pointer, mapping...)
 }
 
 // Structs converts and returns <v> as given struct slice.
-func (v *Var) Structs(pointer interface{}, mapping ...map[string]string) error {
+func (v *VarImp) Structs(pointer interface{}, mapping ...map[string]string) error {
 	return gconv.Structs(v.Val(), pointer, mapping...)
 }
 
 // StructsDeep converts and returns <v> as given struct slice recursively.
-func (v *Var) StructsDeep(pointer interface{}, mapping ...map[string]string) error {
+func (v *VarImp) StructsDeep(pointer interface{}, mapping ...map[string]string) error {
 	return gconv.StructsDeep(v.Val(), pointer, mapping...)
 }
 
@@ -38,7 +38,7 @@ func (v *Var) StructsDeep(pointer interface{}, mapping ...map[string]string) err
 // <pointer> to implement the converting.
 // It calls function Struct if <pointer> is type of *struct/**struct to do the converting.
 // It calls function Structs if <pointer> is type of *[]struct/*[]*struct to do the converting.
-func (v *Var) Scan(pointer interface{}, mapping ...map[string]string) error {
+func (v *VarImp) Scan(pointer interface{}, mapping ...map[string]string) error {
 	return gconv.Scan(v.Val(), pointer, mapping...)
 }
 
@@ -46,6 +46,6 @@ func (v *Var) Scan(pointer interface{}, mapping ...map[string]string) error {
 // parameter <pointer> to implement the converting.
 // It calls function StructDeep if <pointer> is type of *struct/**struct to do the converting.
 // It calls function StructsDeep if <pointer> is type of *[]struct/*[]*struct to do the converting.
-func (v *Var) ScanDeep(pointer interface{}, mapping ...map[string]string) error {
+func (v *VarImp) ScanDeep(pointer interface{}, mapping ...map[string]string) error {
 	return gconv.ScanDeep(v.Val(), pointer, mapping...)
 }
diff --git a/container/gvar/gvar_z_unit_basic_test.go b/container/gvar/gvar_z_unit_basic_test.go
index a3ae8cff4..ebcbd3a1d 100644
--- a/container/gvar/gvar_z_unit_basic_test.go
+++ b/container/gvar/gvar_z_unit_basic_test.go
@@ -19,12 +19,12 @@ import (
 
 func Test_Set(t *testing.T) {
 	gtest.C(t, func(t *gtest.T) {
-		var v gvar.Var
+		var v gvar.VarImp
 		v.Set(123.456)
 		t.Assert(v.Val(), 123.456)
 	})
 	gtest.C(t, func(t *gtest.T) {
-		var v gvar.Var
+		var v gvar.VarImp
 		v.Set(123.456)
 		t.Assert(v.Val(), 123.456)
 	})
@@ -304,7 +304,7 @@ func Test_Duration(t *testing.T) {
 func Test_UnmarshalValue(t *testing.T) {
 	type V struct {
 		Name string
-		Var  *gvar.Var
+		Var  gvar.Var
 	}
 	gtest.C(t, func(t *gtest.T) {
 		var v *V
diff --git a/container/gvar/gvar_z_unit_json_test.go b/container/gvar/gvar_z_unit_json_test.go
index f18bc5546..f05251136 100644
--- a/container/gvar/gvar_z_unit_json_test.go
+++ b/container/gvar/gvar_z_unit_json_test.go
@@ -47,7 +47,7 @@ func Test_Json(t *testing.T) {
 	})
 
 	gtest.C(t, func(t *gtest.T) {
-		var v gvar.Var
+		var v gvar.VarImp
 		s := "i love gf"
 		b, err := json.Marshal(s)
 		t.Assert(err, nil)
diff --git a/database/gdb/gdb.go b/database/gdb/gdb.go
index af41f6d21..3f3e14e38 100644
--- a/database/gdb/gdb.go
+++ b/database/gdb/gdb.go
@@ -173,7 +173,7 @@ type Link interface {
 
 type (
 	// Value is the field value type.
-	Value = *gvar.Var
+	Value = gvar.Var
 
 	// Record is the row record of the table.
 	Record map[string]Value
diff --git a/database/gdb/gdb_core.go b/database/gdb/gdb_core.go
index dd80be6fc..ecdf9a3f7 100644
--- a/database/gdb/gdb_core.go
+++ b/database/gdb/gdb_core.go
@@ -244,12 +244,12 @@ func (c *Core) GetScan(pointer interface{}, sql string, args ...interface{}) err
 func (c *Core) GetValue(sql string, args ...interface{}) (Value, error) {
 	one, err := c.DB.GetOne(sql, args...)
 	if err != nil {
-		return nil, err
+		return gvar.New(nil), err
 	}
 	for _, v := range one {
 		return v, nil
 	}
-	return nil, nil
+	return gvar.New(nil), nil
 }
 
 // GetCount queries and returns the count from database.
diff --git a/database/gdb/gdb_model_select.go b/database/gdb/gdb_model_select.go
index 153ed3da3..c6c3c486d 100644
--- a/database/gdb/gdb_model_select.go
+++ b/database/gdb/gdb_model_select.go
@@ -8,6 +8,7 @@ package gdb
 
 import (
 	"fmt"
+	"github.com/gogf/gf/container/gvar"
 	"github.com/gogf/gf/util/gconv"
 	"reflect"
 )
@@ -118,12 +119,12 @@ func (m *Model) Value(fieldsAndWhere ...interface{}) (Value, error) {
 	}
 	one, err := m.One()
 	if err != nil {
-		return nil, err
+		return gvar.New(nil), err
 	}
 	for _, v := range one {
 		return v, nil
 	}
-	return nil, nil
+	return gvar.New(nil), nil
 }
 
 // Array queries and returns data values as slice from database.
diff --git a/database/gredis/gredis.go b/database/gredis/gredis.go
index c2c53d2cd..181868838 100644
--- a/database/gredis/gredis.go
+++ b/database/gredis/gredis.go
@@ -210,8 +210,8 @@ func (r *Redis) Do(command string, args ...interface{}) (interface{}, error) {
 	return conn.Do(command, args...)
 }
 
-// DoVar returns value from Do as *gvar.Var.
-func (r *Redis) DoVar(command string, args ...interface{}) (*gvar.Var, error) {
+// DoVar returns value from Do as gvar.Var.
+func (r *Redis) DoVar(command string, args ...interface{}) (gvar.Var, error) {
 	v, err := r.Do(command, args...)
 	if result, ok := v.([]byte); ok {
 		return gvar.New(gconv.UnsafeBytesToStr(result)), err
diff --git a/database/gredis/gredis_conn.go b/database/gredis/gredis_conn.go
index 3eb525137..bb4b34944 100644
--- a/database/gredis/gredis_conn.go
+++ b/database/gredis/gredis_conn.go
@@ -44,13 +44,13 @@ func (c *Conn) Do(commandName string, args ...interface{}) (reply interface{}, e
 }
 
 // DoVar retrieves and returns the result from command as gvar.Var.
-func (c *Conn) DoVar(command string, args ...interface{}) (*gvar.Var, error) {
+func (c *Conn) DoVar(command string, args ...interface{}) (gvar.Var, error) {
 	v, err := c.Do(command, args...)
 	return gvar.New(v), err
 }
 
 // ReceiveVar receives a single reply as gvar.Var from the Redis server.
-func (c *Conn) ReceiveVar() (*gvar.Var, error) {
+func (c *Conn) ReceiveVar() (gvar.Var, error) {
 	v, err := c.Receive()
 	return gvar.New(v), err
 }
diff --git a/database/gredis/gredis_z_example_test.go b/database/gredis/gredis_z_example_test.go
index 499d31b34..2f0121ba9 100644
--- a/database/gredis/gredis_z_example_test.go
+++ b/database/gredis/gredis_z_example_test.go
@@ -15,7 +15,7 @@ import (
 func Example_autoMarshalUnmarshalMap() {
 	var (
 		err    error
-		result *gvar.Var
+		result gvar.Var
 		key    = "user"
 		data   = g.Map{
 			"id":   10000,
@@ -40,7 +40,7 @@ func Example_autoMarshalUnmarshalStruct() {
 	}
 	var (
 		err    error
-		result *gvar.Var
+		result gvar.Var
 		key    = "user"
 		user   = &User{
 			Id:   10000,
@@ -71,7 +71,7 @@ func Example_autoMarshalUnmarshalStructSlice() {
 	}
 	var (
 		err    error
-		result *gvar.Var
+		result gvar.Var
 		key    = "user-slice"
 		users1 = []User{
 			{
@@ -104,7 +104,7 @@ func Example_autoMarshalUnmarshalStructSlice() {
 func Example_hashSet() {
 	var (
 		err    error
-		result *gvar.Var
+		result gvar.Var
 		key    = "user"
 	)
 	_, err = g.Redis().Do("HSET", key, "id", 10000)
diff --git a/database/gredis/gredis_z_unit_test.go b/database/gredis/gredis_z_unit_test.go
index 23e5804f0..d62dea30c 100644
--- a/database/gredis/gredis_z_unit_test.go
+++ b/database/gredis/gredis_z_unit_test.go
@@ -356,7 +356,7 @@ func Test_Auto_MarshalSlice(t *testing.T) {
 
 	gtest.C(t, func(t *gtest.T) {
 		var (
-			result *gvar.Var
+			result gvar.Var
 			key    = "user-slice"
 			users1 = []User{
 				{
diff --git a/encoding/gjson/gjson_api.go b/encoding/gjson/gjson_api.go
index 149e19264..81e04f037 100644
--- a/encoding/gjson/gjson_api.go
+++ b/encoding/gjson/gjson_api.go
@@ -68,13 +68,13 @@ func (j *Json) Get(pattern string, def ...interface{}) interface{} {
 	return nil
 }
 
-// GetVar returns a *gvar.Var with value by given <pattern>.
-func (j *Json) GetVar(pattern string, def ...interface{}) *gvar.Var {
+// GetVar returns a gvar.Var with value by given <pattern>.
+func (j *Json) GetVar(pattern string, def ...interface{}) gvar.Var {
 	return gvar.New(j.Get(pattern, def...))
 }
 
-// GetVars returns []*gvar.Var with value by given <pattern>.
-func (j *Json) GetVars(pattern string, def ...interface{}) []*gvar.Var {
+// GetVars returns []gvar.Var with value by given <pattern>.
+func (j *Json) GetVars(pattern string, def ...interface{}) []gvar.Var {
 	return gvar.New(j.Get(pattern, def...)).Vars()
 }
 
diff --git a/frame/g/g.go b/frame/g/g.go
index 06a774c7b..72bdd723b 100644
--- a/frame/g/g.go
+++ b/frame/g/g.go
@@ -10,7 +10,7 @@ import (
 	"github.com/gogf/gf/container/gvar"
 )
 
-// Var is a universal variable type, like generics.
+// Var is a universal variable interface, like generics.
 type Var = gvar.Var
 
 // Frequently-used map type alias.
diff --git a/frame/g/g_func.go b/frame/g/g_func.go
index 728f0dd25..8c008b767 100644
--- a/frame/g/g_func.go
+++ b/frame/g/g_func.go
@@ -13,16 +13,11 @@ import (
 	"github.com/gogf/gf/util/gutil"
 )
 
-// NewVar returns a *gvar.Var.
-func NewVar(i interface{}, safe ...bool) *Var {
+// NewVar returns a gvar.Var.
+func NewVar(i interface{}, safe ...bool) Var {
 	return gvar.New(i, safe...)
 }
 
-// CreateVar returns a gvar.Var.
-func CreateVar(i interface{}, safe ...bool) Var {
-	return gvar.Create(i, safe...)
-}
-
 // Wait blocks until all the web servers shutdown.
 func Wait() {
 	ghttp.Wait()
diff --git a/internal/cmdenv/cmdenv.go b/internal/cmdenv/cmdenv.go
index 7ed521be3..410c3ccd7 100644
--- a/internal/cmdenv/cmdenv.go
+++ b/internal/cmdenv/cmdenv.go
@@ -42,7 +42,7 @@ func doInit() {
 // Fetching Rules:
 // 1. Command line arguments are in lowercase format, eg: gf.<package name>.<variable name>;
 // 2. Environment arguments are in uppercase format, eg: GF_<package name>_<variable name>；
-func Get(key string, def ...interface{}) *gvar.Var {
+func Get(key string, def ...interface{}) gvar.Var {
 	value := interface{}(nil)
 	if len(def) > 0 {
 		value = def[0]
diff --git a/internal/intstore/intstore.go b/internal/intstore/intstore.go
new file mode 100644
index 000000000..e774bab4d
--- /dev/null
+++ b/internal/intstore/intstore.go
@@ -0,0 +1,15 @@
+// Copyright 2020 gf Author(https://github.com/gogf/gf). All Rights Reserved.
+//
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT was not distributed with this file,
+// You can obtain one at https://github.com/gogf/gf.
+
+// Package intstore provides local variable storing for internal usage.
+package intstore
+
+import "reflect"
+
+var (
+	// Reflect type for gvar.VarImp.
+	ReflectTypeVarImp = reflect.Type(nil)
+)
diff --git a/net/ghttp/ghttp_request_param.go b/net/ghttp/ghttp_request_param.go
index f5463cfd2..201bcdc57 100644
--- a/net/ghttp/ghttp_request_param.go
+++ b/net/ghttp/ghttp_request_param.go
@@ -99,7 +99,7 @@ func (r *Request) Get(key string, def ...interface{}) interface{} {
 
 // GetVar is alis of GetRequestVar.
 // See GetRequestVar.
-func (r *Request) GetVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetVar(key string, def ...interface{}) gvar.Var {
 	return r.GetRequestVar(key, def...)
 }
 
diff --git a/net/ghttp/ghttp_request_param_ctx.go b/net/ghttp/ghttp_request_param_ctx.go
index 91910c45d..054949f81 100644
--- a/net/ghttp/ghttp_request_param_ctx.go
+++ b/net/ghttp/ghttp_request_param_ctx.go
@@ -29,7 +29,7 @@ func (r *Request) GetCtx() context.Context {
 // GetCtxVar retrieves and returns a Var with given key name.
 // The optional parameter <def> specifies the default value of the Var if given <key>
 // does not exist in the context.
-func (r *Request) GetCtxVar(key interface{}, def ...interface{}) *gvar.Var {
+func (r *Request) GetCtxVar(key interface{}, def ...interface{}) gvar.Var {
 	value := r.Context().Value(key)
 	if value == nil && len(def) > 0 {
 		value = def[0]
diff --git a/net/ghttp/ghttp_request_param_form.go b/net/ghttp/ghttp_request_param_form.go
index c100160ff..62583a0f0 100644
--- a/net/ghttp/ghttp_request_param_form.go
+++ b/net/ghttp/ghttp_request_param_form.go
@@ -37,7 +37,7 @@ func (r *Request) GetForm(key string, def ...interface{}) interface{} {
 
 // GetFormVar retrieves and returns parameter <key> from form as Var.
 // It returns <def> if <key> does not exist in the form and <def> is given, or else it returns nil.
-func (r *Request) GetFormVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetFormVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(r.GetForm(key, def...))
 }
 
@@ -169,13 +169,13 @@ func (r *Request) GetFormMapStrStr(kvMap ...map[string]interface{}) map[string]s
 	return nil
 }
 
-// GetFormMapStrVar retrieves and returns all form parameters passed from client as map[string]*gvar.Var.
+// GetFormMapStrVar retrieves and returns all form parameters passed from client as map[string]gvar.Var.
 // The parameter <kvMap> specifies the keys retrieving from client parameters, the associated values
 // are the default values if the client does not pass.
-func (r *Request) GetFormMapStrVar(kvMap ...map[string]interface{}) map[string]*gvar.Var {
+func (r *Request) GetFormMapStrVar(kvMap ...map[string]interface{}) map[string]gvar.Var {
 	postMap := r.GetFormMap(kvMap...)
 	if len(postMap) > 0 {
-		m := make(map[string]*gvar.Var, len(postMap))
+		m := make(map[string]gvar.Var, len(postMap))
 		for k, v := range postMap {
 			m[k] = gvar.New(v)
 		}
diff --git a/net/ghttp/ghttp_request_param_param.go b/net/ghttp/ghttp_request_param_param.go
index cd788471f..92f6b1f86 100644
--- a/net/ghttp/ghttp_request_param_param.go
+++ b/net/ghttp/ghttp_request_param_param.go
@@ -29,9 +29,9 @@ func (r *Request) GetParam(key string, def ...interface{}) interface{} {
 	return nil
 }
 
-// GetParamVar returns custom parameter with given name <key> as *gvar.Var.
+// GetParamVar returns custom parameter with given name <key> as gvar.Var.
 // It returns <def> if <key> does not exist.
 // It returns nil if <def> is not passed.
-func (r *Request) GetParamVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetParamVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(r.GetParam(key, def...))
 }
diff --git a/net/ghttp/ghttp_request_param_post.go b/net/ghttp/ghttp_request_param_post.go
index 76d406ad4..46279e4cc 100644
--- a/net/ghttp/ghttp_request_param_post.go
+++ b/net/ghttp/ghttp_request_param_post.go
@@ -39,7 +39,7 @@ func (r *Request) GetPost(key string, def ...interface{}) interface{} {
 }
 
 // Deprecated.
-func (r *Request) GetPostVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetPostVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(r.GetPost(key, def...))
 }
 
@@ -180,15 +180,15 @@ func (r *Request) GetPostMapStrStr(kvMap ...map[string]interface{}) map[string]s
 }
 
 // GetPostMapStrVar retrieves and returns all parameters in the form and body passed from client
-// as map[string]*gvar.Var. The parameter <kvMap> specifies the keys
+// as map[string]gvar.Var. The parameter <kvMap> specifies the keys
 // retrieving from client parameters, the associated values are the default values if the client
 // does not pass.
 //
 // Deprecated.
-func (r *Request) GetPostMapStrVar(kvMap ...map[string]interface{}) map[string]*gvar.Var {
+func (r *Request) GetPostMapStrVar(kvMap ...map[string]interface{}) map[string]gvar.Var {
 	postMap := r.GetPostMap(kvMap...)
 	if len(postMap) > 0 {
-		m := make(map[string]*gvar.Var, len(postMap))
+		m := make(map[string]gvar.Var, len(postMap))
 		for k, v := range postMap {
 			m[k] = gvar.New(v)
 		}
diff --git a/net/ghttp/ghttp_request_param_query.go b/net/ghttp/ghttp_request_param_query.go
index b8250961d..ace74ff55 100644
--- a/net/ghttp/ghttp_request_param_query.go
+++ b/net/ghttp/ghttp_request_param_query.go
@@ -46,7 +46,7 @@ func (r *Request) GetQuery(key string, def ...interface{}) interface{} {
 	return nil
 }
 
-func (r *Request) GetQueryVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetQueryVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(r.GetQuery(key, def...))
 }
 
@@ -172,13 +172,13 @@ func (r *Request) GetQueryMapStrStr(kvMap ...map[string]interface{}) map[string]
 }
 
 // GetQueryMapStrVar retrieves and returns all parameters passed from client using HTTP GET method
-// as map[string]*gvar.Var. The parameter <kvMap> specifies the keys
+// as map[string]gvar.Var. The parameter <kvMap> specifies the keys
 // retrieving from client parameters, the associated values are the default values if the client
 // does not pass.
-func (r *Request) GetQueryMapStrVar(kvMap ...map[string]interface{}) map[string]*gvar.Var {
+func (r *Request) GetQueryMapStrVar(kvMap ...map[string]interface{}) map[string]gvar.Var {
 	queryMap := r.GetQueryMap(kvMap...)
 	if len(queryMap) > 0 {
-		m := make(map[string]*gvar.Var, len(queryMap))
+		m := make(map[string]gvar.Var, len(queryMap))
 		for k, v := range queryMap {
 			m[k] = gvar.New(v)
 		}
diff --git a/net/ghttp/ghttp_request_param_request.go b/net/ghttp/ghttp_request_param_request.go
index ef6fcbfdc..cab6f8448 100644
--- a/net/ghttp/ghttp_request_param_request.go
+++ b/net/ghttp/ghttp_request_param_request.go
@@ -46,9 +46,9 @@ func (r *Request) GetRequest(key string, def ...interface{}) interface{} {
 }
 
 // GetRequestVar retrieves and returns the parameter named <key> passed from client and
-// custom params as *gvar.Var, no matter what HTTP method the client is using. The parameter
+// custom params as gvar.Var, no matter what HTTP method the client is using. The parameter
 // <def> specifies the default value if the <key> does not exist.
-func (r *Request) GetRequestVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetRequestVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(r.GetRequest(key, def...))
 }
 
@@ -247,13 +247,13 @@ func (r *Request) GetRequestMapStrStr(kvMap ...map[string]interface{}) map[strin
 }
 
 // GetRequestMapStrVar retrieves and returns all parameters passed from client and custom
-// params as map[string]*gvar.Var, no matter what HTTP method the client is using. The parameter
+// params as map[string]gvar.Var, no matter what HTTP method the client is using. The parameter
 // <kvMap> specifies the keys retrieving from client parameters, the associated values are the
 // default values if the client does not pass.
-func (r *Request) GetRequestMapStrVar(kvMap ...map[string]interface{}) map[string]*gvar.Var {
+func (r *Request) GetRequestMapStrVar(kvMap ...map[string]interface{}) map[string]gvar.Var {
 	requestMap := r.GetRequestMap(kvMap...)
 	if len(requestMap) > 0 {
-		m := make(map[string]*gvar.Var, len(requestMap))
+		m := make(map[string]gvar.Var, len(requestMap))
 		for k, v := range requestMap {
 			m[k] = gvar.New(v)
 		}
diff --git a/net/ghttp/ghttp_request_param_router.go b/net/ghttp/ghttp_request_param_router.go
index 25b55f81f..e17af66a4 100644
--- a/net/ghttp/ghttp_request_param_router.go
+++ b/net/ghttp/ghttp_request_param_router.go
@@ -22,9 +22,9 @@ func (r *Request) GetRouterValue(key string, def ...interface{}) interface{} {
 	return nil
 }
 
-// GetRouterVar retrieves and returns the router value as *gvar.var with given key name <key>.
+// GetRouterVar retrieves and returns the router value as gvar.Var with given key name <key>.
 // It returns <def> if <key> does not exist.
-func (r *Request) GetRouterVar(key string, def ...interface{}) *gvar.Var {
+func (r *Request) GetRouterVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(r.GetRouterValue(key, def...))
 }
 
diff --git a/os/gbuild/gbuild.go b/os/gbuild/gbuild.go
index 577e1b739..13b2809bc 100644
--- a/os/gbuild/gbuild.go
+++ b/os/gbuild/gbuild.go
@@ -59,8 +59,8 @@ func Get(name string, def ...interface{}) interface{} {
 	return nil
 }
 
-// Get retrieves and returns the build-in binary variable of given name as *gvar.Var.
-func GetVar(name string, def ...interface{}) *gvar.Var {
+// Get retrieves and returns the build-in binary variable of given name as gvar.Var.
+func GetVar(name string, def ...interface{}) gvar.Var {
 	return gvar.New(Get(name, def...))
 }
 
diff --git a/os/gcache/gcache.go b/os/gcache/gcache.go
index 90b9c504d..056de54c8 100644
--- a/os/gcache/gcache.go
+++ b/os/gcache/gcache.go
@@ -40,8 +40,8 @@ func Get(key interface{}) interface{} {
 	return cache.Get(key)
 }
 
-// GetVar retrieves and returns the value of <key> as *gvar.Var.
-func GetVar(key interface{}) *gvar.Var {
+// GetVar retrieves and returns the value of <key> as gvar.Var.
+func GetVar(key interface{}) gvar.Var {
 	return cache.GetVar(key)
 }
 
diff --git a/os/gcache/gcache_mem_cache.go b/os/gcache/gcache_mem_cache.go
index 4afb5c321..a578b2875 100644
--- a/os/gcache/gcache_mem_cache.go
+++ b/os/gcache/gcache_mem_cache.go
@@ -223,8 +223,8 @@ func (c *memCache) Get(key interface{}) interface{} {
 	return nil
 }
 
-// GetVar retrieves and returns the value of <key> as *gvar.Var.
-func (c *memCache) GetVar(key interface{}) *gvar.Var {
+// GetVar retrieves and returns the value of <key> as gvar.Var.
+func (c *memCache) GetVar(key interface{}) gvar.Var {
 	return gvar.New(c.Get(key))
 }
 
diff --git a/os/gcfg/gcfg_api.go b/os/gcfg/gcfg_api.go
index 9956f751f..b28bdce40 100644
--- a/os/gcfg/gcfg_api.go
+++ b/os/gcfg/gcfg_api.go
@@ -23,7 +23,7 @@ func (c *Config) Get(pattern string, def ...interface{}) interface{} {
 	return nil
 }
 
-func (c *Config) GetVar(pattern string, def ...interface{}) *gvar.Var {
+func (c *Config) GetVar(pattern string, def ...interface{}) gvar.Var {
 	if j := c.getJson(); j != nil {
 		return gvar.New(j.Get(pattern, def...))
 	}
diff --git a/os/gcmd/gcmd.go b/os/gcmd/gcmd.go
index b40d8483b..eb7e2b934 100644
--- a/os/gcmd/gcmd.go
+++ b/os/gcmd/gcmd.go
@@ -51,8 +51,8 @@ func GetOpt(name string, def ...string) string {
 	return ""
 }
 
-// GetOptVar returns the option value named <name> as *gvar.Var.
-func GetOptVar(name string, def ...string) *gvar.Var {
+// GetOptVar returns the option value named <name> as gvar.Var.
+func GetOptVar(name string, def ...string) gvar.Var {
 	doInit()
 	return gvar.New(GetOpt(name, def...))
 }
@@ -82,8 +82,8 @@ func GetArg(index int, def ...string) string {
 	return ""
 }
 
-// GetArgVar returns the argument at <index> as *gvar.Var.
-func GetArgVar(index int, def ...string) *gvar.Var {
+// GetArgVar returns the argument at <index> as gvar.Var.
+func GetArgVar(index int, def ...string) gvar.Var {
 	doInit()
 	return gvar.New(GetArg(index, def...))
 }
diff --git a/os/gcmd/gcmd_parser.go b/os/gcmd/gcmd_parser.go
index 73586ff24..d66a7fc6a 100644
--- a/os/gcmd/gcmd_parser.go
+++ b/os/gcmd/gcmd_parser.go
@@ -170,8 +170,8 @@ func (p *Parser) GetOpt(name string, def ...string) string {
 	return ""
 }
 
-// GetOptVar returns the option value named <name> as *gvar.Var.
-func (p *Parser) GetOptVar(name string, def ...interface{}) *gvar.Var {
+// GetOptVar returns the option value named <name> as gvar.Var.
+func (p *Parser) GetOptVar(name string, def ...interface{}) gvar.Var {
 	if p.ContainsOpt(name) {
 		return gvar.New(p.GetOpt(name))
 	}
@@ -203,8 +203,8 @@ func (p *Parser) GetArg(index int, def ...string) string {
 	return ""
 }
 
-// GetArgVar returns the argument at <index> as *gvar.Var.
-func (p *Parser) GetArgVar(index int, def ...string) *gvar.Var {
+// GetArgVar returns the argument at <index> as gvar.Var.
+func (p *Parser) GetArgVar(index int, def ...string) gvar.Var {
 	return gvar.New(p.GetArg(index, def...))
 }
 
diff --git a/os/genv/genv.go b/os/genv/genv.go
index e8b2c183e..f7e16091e 100644
--- a/os/genv/genv.go
+++ b/os/genv/genv.go
@@ -43,7 +43,7 @@ func Get(key string, def ...string) string {
 // GetVar creates and returns a Var with the value of the environment variable
 // named by the <key>. It uses the given <def> if the variable does not exist
 // in the environment.
-func GetVar(key string, def ...interface{}) *gvar.Var {
+func GetVar(key string, def ...interface{}) gvar.Var {
 	v, ok := os.LookupEnv(key)
 	if !ok && len(def) > 0 {
 		return gvar.New(def[0])
diff --git a/os/gsession/gsession_session.go b/os/gsession/gsession_session.go
index 156033f36..23e163946 100644
--- a/os/gsession/gsession_session.go
+++ b/os/gsession/gsession_session.go
@@ -248,7 +248,7 @@ func (s *Session) Get(key string, def ...interface{}) interface{} {
 	return nil
 }
 
-func (s *Session) GetVar(key string, def ...interface{}) *gvar.Var {
+func (s *Session) GetVar(key string, def ...interface{}) gvar.Var {
 	return gvar.New(s.Get(key, def...), true)
 }
 
diff --git a/util/gconv/gconv.go b/util/gconv/gconv.go
index 791a4fd0e..a07992c4d 100644
--- a/util/gconv/gconv.go
+++ b/util/gconv/gconv.go
@@ -12,6 +12,7 @@ package gconv
 import (
 	"encoding/json"
 	"fmt"
+	"github.com/gogf/gf/internal/intstore"
 	"github.com/gogf/gf/os/gtime"
 	"reflect"
 	"strconv"
@@ -251,6 +252,18 @@ func Convert(i interface{}, t string, params ...interface{}) interface{} {
 	case "[]map[string]interface{}":
 		return Maps(i)
 
+	case "gvar.Var":
+		rv := reflect.New(intstore.ReflectTypeVarImp)
+		ri := rv.Interface()
+		if v, ok := ri.(apiSet); ok {
+			v.Set(i)
+		} else if v, ok := ri.(apiUnmarshalValue); ok {
+			v.UnmarshalValue(i)
+		} else {
+			rv.Set(reflect.ValueOf(i))
+		}
+		return ri
+
 	default:
 		return i
 	}
diff --git a/util/gconv/gconv_interface.go b/util/gconv/gconv_interface.go
index b10a600cf..77a22801c 100644
--- a/util/gconv/gconv_interface.go
+++ b/util/gconv/gconv_interface.go
@@ -51,3 +51,8 @@ type apiMapStrAny interface {
 type apiUnmarshalValue interface {
 	UnmarshalValue(interface{}) error
 }
+
+// apiSet is the interface for custom value assignment.
+type apiSet interface {
+	Set(value interface{}) (old interface{})
+}
diff --git a/util/gconv/gconv_struct.go b/util/gconv/gconv_struct.go
index 47375bd78..5d48e015a 100644
--- a/util/gconv/gconv_struct.go
+++ b/util/gconv/gconv_struct.go
@@ -241,34 +241,28 @@ func bindVarToStructAttr(elem reflect.Value, name string, value interface{}) (er
 	return nil
 }
 
-// bindVarToStructByIndex sets value to struct object attribute by index.
-func bindVarToStructByIndex(elem reflect.Value, index int, value interface{}) (err error) {
-	structFieldValue := elem.FieldByIndex([]int{index})
-	if !structFieldValue.IsValid() {
-		return nil
-	}
-	// CanSet checks whether attribute is public accessible.
-	if !structFieldValue.CanSet() {
-		return nil
-	}
-	// If any panic, it secondly uses reflect conversion and assignment.
-	defer func() {
-		if recover() != nil {
-			err = bindVarToReflectValue(structFieldValue, value)
-		}
-	}()
-	if empty.IsNil(value) {
-		structFieldValue.Set(reflect.Zero(structFieldValue.Type()))
-	} else {
-		// It firstly simply assigns the value to the attribute.
-		structFieldValue.Set(reflect.ValueOf(Convert(value, structFieldValue.Type().String())))
-	}
-	return nil
-}
-
 // bindVarToReflectValue sets <value> to reflect value object <structFieldValue>.
 func bindVarToReflectValue(structFieldValue reflect.Value, value interface{}) (err error) {
-	switch structFieldValue.Kind() {
+	kind := structFieldValue.Kind()
+
+	// Converting using interface, for some kinds.
+	switch kind {
+	case reflect.Slice, reflect.Array, reflect.Ptr, reflect.Interface:
+		if !structFieldValue.IsNil() {
+			if v, ok := structFieldValue.Interface().(apiSet); ok {
+				v.Set(value)
+				return nil
+			} else if v, ok := structFieldValue.Interface().(apiUnmarshalValue); ok {
+				err = v.UnmarshalValue(value)
+				if err == nil {
+					return err
+				}
+			}
+		}
+	}
+
+	// Converting by kind.
+	switch kind {
 	case reflect.Struct:
 		if err := Struct(value, structFieldValue); err != nil {
 			// Note there's reflect conversion mechanism here.