CodeLabeledStatement 類別

定義

命名空間:

System.CodeDom

組件:

System.CodeDom.dll

套件:

System.CodeDom v8.0.0

來源:

CodeLabeledStatement.cs

表示標記陳述式 (Label Statement) 或是獨立標記。

public ref class CodeLabeledStatement : System::CodeDom::CodeStatement

public class CodeLabeledStatement : System.CodeDom.CodeStatement

type CodeLabeledStatement = class
    inherit CodeStatement

Public Class CodeLabeledStatement
Inherits CodeStatement

繼承

Object

CodeObject

CodeStatement

CodeLabeledStatement

範例

下列範例程式代碼示範如何使用 CodeGotoStatement 和 CodeLabeledStatement 來重新導向程式流程。

// Declares a type to contain the example code.
CodeTypeDeclaration^ type1 = gcnew CodeTypeDeclaration( "Type1" );

// Declares an entry point method.
CodeEntryPointMethod^ entry1 = gcnew CodeEntryPointMethod;
type1->Members->Add( entry1 );

// Adds a goto statement to continue program flow at the "JumpToLabel" label.
CodeGotoStatement^ goto1 = gcnew CodeGotoStatement( "JumpToLabel" );
entry1->Statements->Add( goto1 );

// Invokes Console.WriteLine to print "Test Output", which is skipped by the goto statement.
array<CodeExpression^>^temp = {gcnew CodePrimitiveExpression( "Test Output." )};
CodeMethodInvokeExpression^ method1 = gcnew CodeMethodInvokeExpression( gcnew CodeTypeReferenceExpression( "System.Console" ),"WriteLine",temp );
entry1->Statements->Add( method1 );

// Declares a label named "JumpToLabel" associated with a method to output a test string using Console.WriteLine.
array<CodeExpression^>^temp2 = {gcnew CodePrimitiveExpression( "Output from labeled statement." )};
CodeMethodInvokeExpression^ method2 = gcnew CodeMethodInvokeExpression( gcnew CodeTypeReferenceExpression( "System.Console" ),"WriteLine",temp2 );
CodeLabeledStatement^ label1 = gcnew CodeLabeledStatement( "JumpToLabel",gcnew CodeExpressionStatement( method2 ) );
entry1->Statements->Add( label1 );

// A C# code generator produces the following source code for the preceeding example code:
//    public class Type1 
//    {
//        
//        public static void Main() 
//        {
//            goto JumpToLabel;
//            System.Console.WriteLine("Test Output");
//            JumpToLabel:
//            System.Console.WriteLine("Output from labeled statement.");
//        }
//    }

// Declares a type to contain the example code.
CodeTypeDeclaration type1 = new CodeTypeDeclaration("Type1");
// Declares an entry point method.
CodeEntryPointMethod entry1 = new CodeEntryPointMethod();
type1.Members.Add( entry1 );
// Adds a goto statement to continue program flow at the "JumpToLabel" label.
CodeGotoStatement goto1 = new CodeGotoStatement("JumpToLabel");
entry1.Statements.Add( goto1 );
// Invokes Console.WriteLine to print "Test Output", which is skipped by the goto statement.
CodeMethodInvokeExpression method1 = new CodeMethodInvokeExpression(
    new CodeTypeReferenceExpression("System.Console"), "WriteLine", new CodePrimitiveExpression("Test Output."));
entry1.Statements.Add( method1 );
// Declares a label named "JumpToLabel" associated with a method to output a test string using Console.WriteLine.
CodeMethodInvokeExpression method2 = new CodeMethodInvokeExpression(
    new CodeTypeReferenceExpression("System.Console"), "WriteLine", new CodePrimitiveExpression("Output from labeled statement."));
CodeLabeledStatement label1 = new CodeLabeledStatement("JumpToLabel", new CodeExpressionStatement(method2) );
entry1.Statements.Add( label1 );

// A C# code generator produces the following source code for the preceeding example code:

//    public class Type1
//    {
//
//        public static void Main()
//        {
//            goto JumpToLabel;
//            System.Console.WriteLine("Test Output");
//            JumpToLabel:
//            System.Console.WriteLine("Output from labeled statement.");
//        }
//    }

' Declares a type to contain the example code.
Dim type1 As New CodeTypeDeclaration("Type1")
' Declares an entry point method.
Dim entry1 As New CodeEntryPointMethod()
type1.Members.Add(entry1)
' Adds a goto statement to continue program flow at the "JumpToLabel" label.
Dim goto1 As New CodeGotoStatement("JumpToLabel")
entry1.Statements.Add(goto1)
' Invokes Console.WriteLine to print "Test Output", which is skipped by the goto statement.
Dim method1 As New CodeMethodInvokeExpression(New CodeTypeReferenceExpression("System.Console"), "WriteLine", New CodePrimitiveExpression("Test Output."))
entry1.Statements.Add(method1)
' Declares a label named "JumpToLabel" associated with a method to output a test string using Console.WriteLine.
Dim method2 As New CodeMethodInvokeExpression(New CodeTypeReferenceExpression("System.Console"), "WriteLine", New CodePrimitiveExpression("Output from labeled statement."))
Dim label1 As New CodeLabeledStatement("JumpToLabel", New CodeExpressionStatement(method2))
entry1.Statements.Add(label1)

' A Visual Basic code generator produces the following source code for the preceeding example code:

'   Public Class Type1
'
'       Public Shared Sub Main()
'           GoTo JumpToLabel
'           System.Console.WriteLine("Test Output")
'           JumpToLabel:
'           System.Console.WriteLine("Output from labeled statement.")
'       End Sub
'   End Class

備註

CodeLabeledStatement 表示標籤，並選擇性地表示相關聯的語句。 標籤可用來表示 的目標 CodeGotoStatement。

Statement 是選用屬性。 若要只建立標籤，請將 屬性保留 Statement 為未初始化。

注意

並非所有語言都支援goto語句和標籤，因此您應該使用 旗標呼叫 Supports 方法來GotoStatements測試程式代碼產生器是否支援 goto 語句和標籤。

建構函式

CodeLabeledStatement()	初始化 CodeLabeledStatement 類別的新執行個體。
CodeLabeledStatement(String)	使用指定的標記名稱，初始化 CodeLabeledStatement 類別的新執行個體。
CodeLabeledStatement(String, CodeStatement)	使用指定的標記和陳述式，初始化 CodeLabeledStatement 類別的新執行個體。

屬性

EndDirectives	取得包含結尾指示詞的 CodeDirectiveCollection 物件。 (繼承來源 CodeStatement)
Label	取得或設定標記名稱。
LinePragma	取得或設定程式碼陳述式發生所在的行。 (繼承來源 CodeStatement)
StartDirectives	取得包含開頭指示詞的 CodeDirectiveCollection 物件。 (繼承來源 CodeStatement)
Statement	取得或設定選擇性相關陳述式。
UserData	取得目前物件的使用者可定義資料。 (繼承來源 CodeObject)

方法

Equals(Object)	判斷指定的物件是否等於目前的物件。 (繼承來源 Object)
GetHashCode()	做為預設雜湊函式。 (繼承來源 Object)
GetType()	取得目前執行個體的 Type。 (繼承來源 Object)
MemberwiseClone()	建立目前 Object 的淺層複製。 (繼承來源 Object)
ToString()	傳回代表目前物件的字串。 (繼承來源 Object)

另請參閱

• CodeGotoStatement