在编写c#代码过程中，我们经常需要做一些重复枯燥的工作。例如，编写DTO（数据访问对象），通常就是为一个类定义一系列的变量和属性。
有一些第三方的IDE辅助工具，可以为我们生成一些代码，减少工作量。例如，Assist X就是一款很值得推荐的工具，使用其提供的Encapsulate Field功能，可以很方便地将一个类地编写封装为属性。
我今天需要介绍的如何使用Visual Studio 2005 IDE中自带的宏实现类似的功能。
打开Visual Studio 2005 IDE，选择“工具” > "宏" > “宏 IDE”，选择“添加模块”。例如，我是在MyMacros项目中新增了一个EditorHelper模块，代码如下：
Imports System
Imports EnvDTE
Imports EnvDTE80
Imports System.Diagnostics
Public Module EditorHelper
'为一个参数封装一般属性访问器
Public Sub EncapsulateField()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Try
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementVariable)
If (codeElement Is Nothing) Then
Return
End If
Debug.Assert(codeElement.Kind = vsCMElement.vsCMElementVariable)
Dim codeVar As CodeVariable = CType(codeElement, CodeVariable)
Dim fieldName As String = codeVar.Name
Dim codeClass As CodeClass = CType(codeVar.Parent, CodeClass)
AddPropertyToClass(codeClass, fieldName, codeVar.Type)
Catch ex As Exception
'吃掉异常，不做处理或者提示
End Try
End Sub
Public Sub EncapsulateAllFields()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
Try
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementClass)
Dim codeClass As CodeClass = CType(codeElement, CodeClass)
Dim i As Integer
For i = 1 To codeClass.Members.Count
'如果属性已经定义，会抛出异常
'在这里处理异常，即使新增的属性已经定义，也可以继续处理下面的代码
Try
Dim element As CodeElement = codeClass.Members.Item(i)
If (element.Kind = vsCMElement.vsCMElementVariable) Then
Dim codeVariable As CodeVariable = CType(element, CodeVariable)
If (Not codeVariable.IsShared) Then '静态变量不需要增加属性
AddPropertyToClass(codeClass, codeVariable.Name, codeVariable.Type)
End If
End If
Catch ex As Exception
'吃掉异常
End Try
Next
Catch ex As Exception
'可能并没有选择有效的类定义，这时会抛出异常，忽略
End Try
End Sub
'根据成员的名称的类型，在类对象中插入属性
Private Sub AddPropertyToClass(ByVal codeClass As CodeClass, ByVal fieldName As String, ByVal fieldType As Object)
'生成属性的名称，规则是首先字母大写。如果变量的开头为“_”，移除
Dim propertyName As String = fieldName
If (propertyName.StartsWith("_")) Then
propertyName = propertyName.TrimStart("_"c)
End If
propertyName = propertyName.Substring(0, 1).ToUpper() & propertyName.Substring(1)
'创建属性对象
'-1表示代码插入到类的最下方
'vsCMAccess.vsCMAccessPublic表示为public
Dim codeProperty As CodeProperty = codeClass.AddProperty(propertyName, propertyName, fieldType, -1, vsCMAccess.vsCMAccessPublic)
'Getter
Dim getter As CodeFunction = codeProperty.Getter
Dim getterPoint As TextPoint = getter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim getterEditPoint As EditPoint = getterPoint.CreateEditPoint()
getterEditPoint.Delete(getter.GetEndPoint(vsCMPart.vsCMPartBody))
getterEditPoint.Insert(vbCrLf) '插入回车符
getterEditPoint.LineUp()
getterEditPoint.Indent(, 4) '缩进4个位置
getterEditPoint.Insert("return " & fieldName & ";")
'Setter
Dim setter As CodeFunction = codeProperty.Setter
Dim setterPoint As TextPoint = setter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim setterEditPoint As EditPoint = setterPoint.CreateEditPoint()
setterEditPoint.Insert(vbCrLf) '插入回车符
setterEditPoint.LineUp()
setterEditPoint.Indent(, 4) '缩进4个位置
setterEditPoint.Insert(fieldName & " = value;")
End Sub
End Module
Imports EnvDTE
Imports EnvDTE80
Imports System.Diagnostics
Public Module EditorHelper
'为一个参数封装一般属性访问器
Public Sub EncapsulateField()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Try
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementVariable)
If (codeElement Is Nothing) Then
Return
End If
Debug.Assert(codeElement.Kind = vsCMElement.vsCMElementVariable)
Dim codeVar As CodeVariable = CType(codeElement, CodeVariable)
Dim fieldName As String = codeVar.Name
Dim codeClass As CodeClass = CType(codeVar.Parent, CodeClass)
AddPropertyToClass(codeClass, fieldName, codeVar.Type)
Catch ex As Exception
'吃掉异常，不做处理或者提示
End Try
End Sub
Public Sub EncapsulateAllFields()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
Try
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementClass)
Dim codeClass As CodeClass = CType(codeElement, CodeClass)
Dim i As Integer
For i = 1 To codeClass.Members.Count
'如果属性已经定义，会抛出异常
'在这里处理异常，即使新增的属性已经定义，也可以继续处理下面的代码
Try
Dim element As CodeElement = codeClass.Members.Item(i)
If (element.Kind = vsCMElement.vsCMElementVariable) Then
Dim codeVariable As CodeVariable = CType(element, CodeVariable)
If (Not codeVariable.IsShared) Then '静态变量不需要增加属性
AddPropertyToClass(codeClass, codeVariable.Name, codeVariable.Type)
End If
End If
Catch ex As Exception
'吃掉异常
End Try
Next
Catch ex As Exception
'可能并没有选择有效的类定义，这时会抛出异常，忽略
End Try
End Sub
'根据成员的名称的类型，在类对象中插入属性
Private Sub AddPropertyToClass(ByVal codeClass As CodeClass, ByVal fieldName As String, ByVal fieldType As Object)
'生成属性的名称，规则是首先字母大写。如果变量的开头为“_”，移除
Dim propertyName As String = fieldName
If (propertyName.StartsWith("_")) Then
propertyName = propertyName.TrimStart("_"c)
End If
propertyName = propertyName.Substring(0, 1).ToUpper() & propertyName.Substring(1)
'创建属性对象
'-1表示代码插入到类的最下方
'vsCMAccess.vsCMAccessPublic表示为public
Dim codeProperty As CodeProperty = codeClass.AddProperty(propertyName, propertyName, fieldType, -1, vsCMAccess.vsCMAccessPublic)
'Getter
Dim getter As CodeFunction = codeProperty.Getter
Dim getterPoint As TextPoint = getter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim getterEditPoint As EditPoint = getterPoint.CreateEditPoint()
getterEditPoint.Delete(getter.GetEndPoint(vsCMPart.vsCMPartBody))
getterEditPoint.Insert(vbCrLf) '插入回车符
getterEditPoint.LineUp()
getterEditPoint.Indent(, 4) '缩进4个位置
getterEditPoint.Insert("return " & fieldName & ";")
'Setter
Dim setter As CodeFunction = codeProperty.Setter
Dim setterPoint As TextPoint = setter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim setterEditPoint As EditPoint = setterPoint.CreateEditPoint()
setterEditPoint.Insert(vbCrLf) '插入回车符
setterEditPoint.LineUp()
setterEditPoint.Indent(, 4) '缩进4个位置
setterEditPoint.Insert(fieldName & " = value;")
End Sub
End Module
我定义了两个Public方法：EncapsulateField和EncapsulateAllFields，分别用于为类的一个变量封装属性，或者为类中所有的变量（非静态）封装属性。
使用上面的宏的方法很简单，选择“工具”>“宏”>“宏资源管理器”就可以看到我们已经创建的宏方法，如下图所示：
假如你已经编写了这样一段代码：
using System;
using System.Collections.Generic;
using System.Text;
namespace Demo
{
public class Person
{
private int _id;
private string _name;
private DateTime _birthDay;
}
}
using System.Collections.Generic;
using System.Text;
namespace Demo
{
public class Person
{
private int _id;
private string _name;
private DateTime _birthDay;
}
}
将光标移到“_name”变量上，然后双击“EncapsulateField”宏，就运行了该宏。运行后，你可以得到这样的代码：
using System;
using System.Collections.Generic;
using System.Text;
namespace Demo
{
public class Person
{
private int _id;
private string _name;
private DateTime _birthDay;
public string Name
{
get
{
return _name;
}
set
{
_name = value;
}
}
}
}
using System.Collections.Generic;
using System.Text;
namespace Demo
{
public class Person
{
private int _id;
private string _name;
private DateTime _birthDay;
public string Name
{
get
{
return _name;
}
set
{
_name = value;
}
}
}
}
可以看到“EncapsulateField”宏已经为private string _name;创建了相应的属性。
EncapsulateAllFields宏只需要将光标放在Person类的代码区域中，就可以正常执行。例如针对上面的代码，EncapsulateAllFields后可以为Person类中的每一个变量都生成相应的属性。（注：上面的代码中Name属性已经有定义，所有试图再添加Name属性时会抛出异常，在EncapsulateAllFields宏定义中，已经将该异常吃掉，所以，可以正确地为所有变量生成属性）。运行后的代码如下：
using System;
using System.Collections.Generic;
using System.Text;
namespace Demo
{
public class Person
{
private int _id;
private string _name;
private DateTime _birthDay;
public string Name
{
get
{
return _name;
}
set
{
_name = value;
}
}
public int Id
{
get
{
return _id;
}
set
{
_id = value;
}
}
public System.DateTime BirthDay
{
get
{
return _birthDay;
}
set
{
_birthDay = value;
}
}
}
}
using System.Collections.Generic;
using System.Text;
namespace Demo
{
public class Person
{
private int _id;
private string _name;
private DateTime _birthDay;
public string Name
{
get
{
return _name;
}
set
{
_name = value;
}
}
public int Id
{
get
{
return _id;
}
set
{
_id = value;
}
}
public System.DateTime BirthDay
{
get
{
return _birthDay;
}
set
{
_birthDay = value;
}
}
}
}
在确认上面的宏可以正确运行的情况下，我们还可以为其定义快捷键，进一步提高我们的工作效率。
在Visual Studio 2005 IDE中选择“工具” > “选项”
在“选项”对话框中选择“环境”>“键盘”。
在【显示命令包含】中输入Encap...，可以帮你快速定位到相应的宏命令；
【新快捷键用于】选项中选择“文本编辑器”；
激活【按快捷键】输入框，选择你所希望的快捷键，例如我这里为EncapsulateField定义的快捷键为“Ctrl + `”，为EncapsulateAllFields定义的快捷键为“Ctrl + Shift + `”
点击分配按钮
你就可以在文本编辑器中尽情享用宏给你带来的方便。
补充在Visual Studio 2003中使用的宏：
Visual Studio 2003 IDE与Visual Studio 2005 IDE在处理上稍微有些不一致的地方，需要做如下的调整：
Imports System
Imports EnvDTE
Imports System.Diagnostics
Public Module EditorHelper
'为一个参数封装一般属性访问器
Public Sub EncapsulateField()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Try
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementVariable)
If (codeElement Is Nothing) Then
Return
End If
Debug.Assert(codeElement.Kind = vsCMElement.vsCMElementVariable)
Dim codeVar As CodeVariable = CType(codeElement, CodeVariable)
Dim fieldName As String = codeVar.Name
Dim codeClass As CodeClass = CType(codeVar.Parent, CodeClass)
AddPropertyToClass(codeClass, fieldName, codeVar.Type)
Catch ex As Exception
'吃掉异常，不做处理或者提示
MsgBox(ex.Message)
End Try
End Sub
Public Sub EncapsulateAllFields()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
Try
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementClass)
Dim codeClass As CodeClass = CType(codeElement, CodeClass)
Dim i As Integer
For i = 1 To codeClass.Members.Count
'如果属性已经定义，会抛出异常
'在这里处理异常，即使新增的属性已经定义，也可以继续处理下面的代码
Try
Dim element As CodeElement = codeClass.Members.Item(i)
If (element.Kind = vsCMElement.vsCMElementVariable) Then
Dim codeVariable As CodeVariable = CType(element, CodeVariable)
If (Not codeVariable.IsShared) Then '静态变量不需要增加属性
AddPropertyToClass(codeClass, codeVariable.Name, codeVariable.Type)
End If
End If
Catch ex As Exception
'吃掉异常
End Try
Next
Catch ex As Exception
'可能并没有选择有效的类定义，这时会抛出异常，忽略
MsgBox(ex.Message)
End Try
End Sub
'根据成员的名称的类型，在类对象中插入属性
Private Sub AddPropertyToClass(ByVal codeClass As CodeClass, ByVal fieldName As String, ByVal fieldType As Object)
'生成属性的名称，规则是首先字母大写。如果变量的开头为“_”，移除
Dim propertyName As String = fieldName
If (propertyName.StartsWith("_")) Then
propertyName = propertyName.TrimStart("_"c)
End If
propertyName = propertyName.Substring(0, 1).ToUpper() & propertyName.Substring(1)
'创建属性对象
'-1表示代码插入到类的最下方
'vsCMAccess.vsCMAccessPublic表示为public
Dim codeProperty As CodeProperty = codeClass.AddProperty(propertyName, propertyName, fieldType, -1, vsCMAccess.vsCMAccessPublic)
'Getter
Dim getter As CodeFunction = codeProperty.Getter
Dim getterPoint As TextPoint = getter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim getterEditPoint As EditPoint = getterPoint.CreateEditPoint()
getterEditPoint.Delete(getter.GetEndPoint(vsCMPart.vsCMPartBody))
getterEditPoint.Insert("get{ return " & fieldName & "; }")
'Setter
Dim setter As CodeFunction = codeProperty.Setter
Dim setterPoint As TextPoint = setter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim setterEditPoint As EditPoint = setterPoint.CreateEditPoint()
setterEditPoint.Delete(setter.GetEndPoint(vsCMPart.vsCMPartBody))
setterEditPoint.Insert("set{ " & fieldName & " = value; }")
End Sub
End Module
Imports EnvDTE
Imports System.Diagnostics
Public Module EditorHelper
'为一个参数封装一般属性访问器
Public Sub EncapsulateField()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Try
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementVariable)
If (codeElement Is Nothing) Then
Return
End If
Debug.Assert(codeElement.Kind = vsCMElement.vsCMElementVariable)
Dim codeVar As CodeVariable = CType(codeElement, CodeVariable)
Dim fieldName As String = codeVar.Name
Dim codeClass As CodeClass = CType(codeVar.Parent, CodeClass)
AddPropertyToClass(codeClass, fieldName, codeVar.Type)
Catch ex As Exception
'吃掉异常，不做处理或者提示
MsgBox(ex.Message)
End Try
End Sub
Public Sub EncapsulateAllFields()
Dim projectItem As ProjectItem = DTE.ActiveDocument.ProjectItem
Dim fileCodeModel As FileCodeModel = projectItem.FileCodeModel
Try
'得到当前选定的内容
Dim selectText As TextSelection = DTE.ActiveDocument.Selection
'获取到当前光标的位置
Dim point As TextPoint = selectText.ActivePoint
Dim codeElement As CodeElement = fileCodeModel.CodeElementFromPoint(point, vsCMElement.vsCMElementClass)
Dim codeClass As CodeClass = CType(codeElement, CodeClass)
Dim i As Integer
For i = 1 To codeClass.Members.Count
'如果属性已经定义，会抛出异常
'在这里处理异常，即使新增的属性已经定义，也可以继续处理下面的代码
Try
Dim element As CodeElement = codeClass.Members.Item(i)
If (element.Kind = vsCMElement.vsCMElementVariable) Then
Dim codeVariable As CodeVariable = CType(element, CodeVariable)
If (Not codeVariable.IsShared) Then '静态变量不需要增加属性
AddPropertyToClass(codeClass, codeVariable.Name, codeVariable.Type)
End If
End If
Catch ex As Exception
'吃掉异常
End Try
Next
Catch ex As Exception
'可能并没有选择有效的类定义，这时会抛出异常，忽略
MsgBox(ex.Message)
End Try
End Sub
'根据成员的名称的类型，在类对象中插入属性
Private Sub AddPropertyToClass(ByVal codeClass As CodeClass, ByVal fieldName As String, ByVal fieldType As Object)
'生成属性的名称，规则是首先字母大写。如果变量的开头为“_”，移除
Dim propertyName As String = fieldName
If (propertyName.StartsWith("_")) Then
propertyName = propertyName.TrimStart("_"c)
End If
propertyName = propertyName.Substring(0, 1).ToUpper() & propertyName.Substring(1)
'创建属性对象
'-1表示代码插入到类的最下方
'vsCMAccess.vsCMAccessPublic表示为public
Dim codeProperty As CodeProperty = codeClass.AddProperty(propertyName, propertyName, fieldType, -1, vsCMAccess.vsCMAccessPublic)
'Getter
Dim getter As CodeFunction = codeProperty.Getter
Dim getterPoint As TextPoint = getter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim getterEditPoint As EditPoint = getterPoint.CreateEditPoint()
getterEditPoint.Delete(getter.GetEndPoint(vsCMPart.vsCMPartBody))
getterEditPoint.Insert("get{ return " & fieldName & "; }")
'Setter
Dim setter As CodeFunction = codeProperty.Setter
Dim setterPoint As TextPoint = setter.GetStartPoint(vsCMPart.vsCMPartBody)
Dim setterEditPoint As EditPoint = setterPoint.CreateEditPoint()
setterEditPoint.Delete(setter.GetEndPoint(vsCMPart.vsCMPartBody))
setterEditPoint.Insert("set{ " & fieldName & " = value; }")
End Sub
End Module
另外，在2003中使用EncapsulateAllFields的宏时，也需要注意一点：在使用时，光标的应该停留在类定义的空白位置，否则使用Dim codeClass As CodeClass = CType(codeElement, CodeClass)方法不能正确获取到类对象（例如，如果光标在构造函数里，获取到的是构造函数对象，这点与2005还是有所区别的）。
参考：
《用Visual Studio 2005创建宏代码生成器》：转载太多，已经不知道原出处