CodeFunction.MustImplement 属性

项目
10/25/2012

设置或获取一个值，它指示该项是否被声明为抽象而需要实现。

命名空间： EnvDTE
程序集： EnvDTE（在 EnvDTE.dll 中）

语法

声明
Property MustImplement As Boolean

bool MustImplement { get; set; }

property bool MustImplement {
    bool get ();
    void set (bool value);
}

abstract MustImplement : bool with get, set

function get MustImplement () : boolean
function set MustImplement (value : boolean)

属性值

类型：System.Boolean
一个布尔值，如果方法声明为抽象而需要实现，则为 true；否则为 false。

备注

MustImplement 返回或设置是实现了该方法还是要求子类中的实现。请注意，对于某些语言，它可能始终是 False，而且设置 MustImplement 可能会失败，具体取决于语言。

说明
在进行某些类型的编辑之后，代码模型元素（如类、结构、函数、特性、委托等）的值可能是非确定性的，这意味着不能指望它们的值总是保持不变。有关更多信息，请参见使用代码模型查找代码 (Visual Basic) 中的“代码模型元素的值可能会更改”一节。

示例

 Sub MustImplementExample(ByVal dte As DTE2)

    ' Before running this example, open a code document from a project
    ' and place the insertion point inside a class definition.
    Try
        ' Retrieve the CodeClass at the insertion point.
        Dim sel As TextSelection = _
            CType(dte.ActiveDocument.Selection, TextSelection)
        Dim cls As CodeClass = _
            CType(sel.ActivePoint.CodeElement( _
            vsCMElement.vsCMElementClass), CodeClass)

        Dim mustImpl As String
        Dim elem As CodeElement
        For Each elem In cls.Members
            If (elem.Kind = vsCMElement.vsCMElementFunction) Then
                Dim fun As CodeFunction = CType(elem, CodeFunction)
                If fun.MustImplement Then
                    mustImpl &= fun.Prototype( _
                        vsCMPrototype.vsCMPrototypeParamNames Or _
                        vsCMPrototype.vsCMPrototypeParamTypes Or _
                        vsCMPrototype.vsCMPrototypeType) & vbCrLf
                End If
            End If
        Next

        MsgBox(cls.Name & " has the following abstract methods:" & _
            vbCrLf & vbCrLf & mustImpl)
    Catch ex As Exception
        MsgBox(ex.Message)
    End Try

End Sub

 public void MustImplementExample(DTE2 dte)
{
    // Before running this example, open a code document from a project
    // and place the insertion point inside a class definition.
    try
    {
        // Retrieve the CodeClass at the insertion point.
        TextSelection sel = 
            (TextSelection)dte.ActiveDocument.Selection;
        CodeClass cls = 
            (CodeClass)sel.ActivePoint.get_CodeElement(
            vsCMElement.vsCMElementClass);
        string mustImpl = "";

        foreach (CodeElement elem in cls.Members)
        {
            if (elem.Kind == vsCMElement.vsCMElementFunction)
            {
                CodeFunction fun = (CodeFunction)elem;

                if (fun.MustImplement)
                    mustImpl += fun.get_Prototype(
                        (int)(vsCMPrototype.vsCMPrototypeParamNames | 
                        vsCMPrototype.vsCMPrototypeParamTypes | 
                        vsCMPrototype.vsCMPrototypeType)) + "\n";
            }
        }

        MessageBox.Show(cls.Name + 
            " has the following abstract methods:\n\n" + mustImpl);
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}