1 | #Region "Microsoft.VisualBasic::955cb25b01fa63265ea9a9affab86884, Microsoft.VisualBasic.Core\ComponentModel\DataSource\Property\PropertyValue.vb" |
2 | |
3 | ' Author: |
4 | ' |
5 | ' asuka (amethyst.asuka@gcmodeller.org) |
6 | ' xie (genetics@smrucc.org) |
7 | ' xieguigang (xie.guigang@live.com) |
8 | ' |
9 | ' Copyright (c) 2018 GPL3 Licensed |
10 | ' |
11 | ' |
12 | ' GNU GENERAL PUBLIC LICENSE (GPL3) |
13 | ' |
14 | ' |
15 | ' This program is free software: you can redistribute it and/or modify |
16 | ' it under the terms of the GNU General Public License as published by |
17 | ' the Free Software Foundation, either version 3 of the License, or |
18 | ' (at your option) any later version. |
19 | ' |
20 | ' This program is distributed in the hope that it will be useful, |
21 | ' but WITHOUT ANY WARRANTY; without even the implied warranty of |
22 | ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
23 | ' GNU General Public License for more details. |
24 | ' |
25 | ' You should have received a copy of the GNU General Public License |
26 | ' along with this program. If not, see <http://www.gnu.org/licenses/>. |
27 | |
28 | |
29 | |
30 | ' /********************************************************************************/ |
31 | |
32 | ' Summaries: |
33 | |
34 | ' Class PropertyValue |
35 | ' |
36 | ' Properties: obj, value |
37 | ' |
38 | ' Constructor: (+2 Overloads) Sub New |
39 | ' |
40 | ' Function: [New], GetValue, (+2 Overloads) Read, SetValue, ToString |
41 | ' |
42 | ' Sub: SetValue |
43 | ' |
44 | ' |
45 | ' /********************************************************************************/ |
46 | |
47 | #End Region |
48 | |
49 | Imports System.Reflection |
50 | Imports Microsoft.VisualBasic.Language |
51 | Imports Microsoft.VisualBasic.Serialization.JSON |
52 | |
53 | Namespace ComponentModel.DataSourceModel |
54 | |
55 | ''' <summary> |
56 | ''' The <see cref="PropertyInfo"/> like definition of the extension property. |
57 | ''' </summary> |
58 | ''' <typeparam name="T"></typeparam> |
59 | Public Class PropertyValue(Of T) : Inherits Value(Of T) |
60 | |
61 | ReadOnly __get As Func(Of T) |
62 | ReadOnly __set As Action(Of T) |
63 | |
64 | ''' <summary> |
65 | ''' The Extension property value. |
66 | ''' </summary> |
67 | ''' <returns></returns> |
68 | Public Overrides Property value As T |
69 | Get |
70 | Return __get() |
71 | End Get |
72 | Set(value As T) |
73 | MyBase.value = value |
74 | |
75 | If Not __set Is Nothing Then |
76 | Call __set(value) ' 因为在初始化的时候会对这个属性赋值,但是set没有被初始化,所以会出错,在这里加了一个if判断来避免空引用的错误 |
77 | End If |
78 | End Set |
79 | End Property |
80 | |
81 | ''' <summary> |
82 | ''' The instance object for this extension property |
83 | ''' </summary> |
84 | ''' <returns></returns> |
85 | Public Property obj As IClassObject |
86 | |
87 | ''' <summary> |
88 | ''' Custom property value.(value generated based on the extension property host <see cref="obj"/>) |
89 | ''' </summary> |
90 | ''' <param name="[get]">请勿使用<see cref="GetValue"/></param>函数,否则会出现栈空间溢出 |
91 | ''' <param name="[set]">请勿使用<see cref="SetValue"/></param>方法,否则会出现栈空间溢出 |
92 | Sub New([get] As Func(Of T), [set] As Action(Of T)) |
93 | __get = [get] |
94 | __set = [set] |
95 | End Sub |
96 | |
97 | ''' <summary> |
98 | ''' Tag property value.(默认是将数据写入到基本类型的值之中) |
99 | ''' </summary> |
100 | Sub New() |
101 | __get = Function() MyBase.value |
102 | __set = Sub(v) MyBase.value = v |
103 | End Sub |
104 | |
105 | ''' <summary> |
106 | ''' 这个主要是应用于Linq表达式之中,将属性值设置之后返回宿主对象实例 |
107 | ''' </summary> |
108 | ''' <param name="value"></param> |
109 | ''' <returns></returns> |
110 | Public Function SetValue(value As T) As IClassObject |
111 | Call __set(value) |
112 | Return obj |
113 | End Function |
114 | |
115 | ''' <summary> |
116 | ''' Property Get Value |
117 | ''' </summary> |
118 | ''' <param name="x"></param> |
119 | ''' <returns></returns> |
120 | Public Overloads Shared Narrowing Operator CType(x As PropertyValue(Of T)) As T |
121 | Return x.value |
122 | End Operator |
123 | |
124 | ''' <summary> |
125 | ''' <see cref="Value"/> -> <see cref="GetObjectJson"/> |
126 | ''' </summary> |
127 | ''' <returns></returns> |
128 | Public Overrides Function ToString() As String |
129 | Return value.GetJson |
130 | End Function |
131 | |
132 | Public Shared Function GetValue(Of Cls As IClassObject)(x As Cls, name As String) As PropertyValue(Of T) |
133 | Dim value As Object = x.Extension.DynamicHashTable(name) |
134 | Dim pv As PropertyValue(Of T) = DirectCast(value, PropertyValue(Of T)) |
135 | Return pv |
136 | End Function |
137 | |
138 | Public Shared Sub SetValue(Of Cls As IClassObject)(x As Cls, name As String, value As T) |
139 | Dim pvo As Object = x.Extension.DynamicHashTable(name) |
140 | Dim pv As PropertyValue(Of T) = DirectCast(pvo, PropertyValue(Of T)) |
141 | pv.value = value |
142 | End Sub |
143 | |
144 | ''' <summary> |
145 | ''' Creates a new extension property for the target <see cref="BaseClass"/> |
146 | ''' </summary> |
147 | ''' <typeparam name="Cls"></typeparam> |
148 | ''' <param name="x"></param> |
149 | ''' <param name="name"></param> |
150 | ''' <returns></returns> |
151 | Public Shared Function [New](Of Cls As IClassObject)(x As Cls, name As String) As PropertyValue(Of T) |
152 | Dim value As New PropertyValue(Of T)() |
153 | x.Extension.DynamicHashTable(name) = value |
154 | value.obj = x |
155 | Return value |
156 | End Function |
157 | |
158 | ''' <summary> |
159 | ''' Gets the tag property value from the <see cref="BaseClass"/>.(读取<see cref="BaseClass"/>对象之中的一个拓展属性) |
160 | ''' </summary> |
161 | ''' <typeparam name="Cls"></typeparam> |
162 | ''' <param name="x"></param> |
163 | ''' <param name="name"></param> |
164 | ''' <returns></returns> |
165 | Public Shared Function Read(Of Cls As IClassObject)(x As Cls, name As String) As PropertyValue(Of T) |
166 | If x.Extension Is Nothing Then |
167 | x.Extension = New ExtendedProps |
168 | End If |
169 | Dim prop As Object = x.Extension.DynamicHashTable(name) |
170 | If prop Is Nothing Then |
171 | prop = PropertyValue(Of T).[New](Of Cls)(x, name) |
172 | End If |
173 | Return DirectCast(prop, PropertyValue(Of T)) |
174 | End Function |
175 | |
176 | Public Shared Function Read(Of Cls As IClassObject)(x As Cls, pm As MethodBase) As PropertyValue(Of T) |
177 | Return Read(Of Cls)(x, pm.Name) |
178 | End Function |
179 | End Class |
180 | End Namespace |