ExceptionHandlingClauseとは? わかりやすく解説

ExceptionHandlingClause クラス

メモ : このクラスは、.NET Framework version 2.0 で新しく追加されたものです。

構造化例外処理ブロック内の句を表します。

名前空間: System.Reflection
アセンブリ: mscorlib (mscorlib.dll 内)
構文構文

<ComVisibleAttribute(True)> _
Public NotInheritable Class
 ExceptionHandlingClause
Dim instance As ExceptionHandlingClause
[ComVisibleAttribute(true)] 
public sealed class ExceptionHandlingClause
[ComVisibleAttribute(true)] 
public ref class ExceptionHandlingClause sealed
/** @attribute ComVisibleAttribute(true) */ 
public final class ExceptionHandlingClause
ComVisibleAttribute(true) 
public final class ExceptionHandlingClause
解説解説

ExceptionHandlingClause クラスは、try…catch…finally ブロック (Visual Basic では Try…Catch…Finally) 内の句に関する情報を提供します。メソッド内の例外処理句の一覧を取得するには、そのメソッドを表す MethodInfo を取得します。GetMethodBody メソッドを使用して、MethodBody オブジェクトを取得し、次に ExceptionHandlingClauses プロパティを使用して句の一覧を取得します。

メモメモ

例外処理句を処理するには、メタデータと MSIL (Microsoft Intermediate Language) の命令書式について十分に理解している必要があります。この情報については、共通言語基盤 (CLI: Common Language Infrastructure) のドキュメント、特に「Partition II: Metadata Definition and Semantics」と「Partition III: CIL Instruction Set」を参照してください。このドキュメントは、http://msdn.microsoft.com/net/ecma/ および http://www.ecma-international.org/publications/standards/Ecma-335.htm で入手できます。

使用例使用例

MethodBodyExample という名前のテスト メソッドを定義し、ローカル変数の情報および例外処理句を表示するコード例を次に示します。MethodBase.GetMethodBody メソッドを使用して、テスト メソッドの MethodBody オブジェクトを取得します。ExceptionHandlingClauses プロパティは、ExceptionHandlingClause オブジェクトの一覧を取得し、それらのプロパティを表示するために使用されます。

Ildasm.exe を使用すると、コンパイルしたコード例の MSIL を調べて、オフセットと長さの計算方法を確認できます。

メモメモ

すべてのコンピュータ言語が ExceptionHandlingClauseOptions.Filter 句を生成できるわけではありません。Visual Basic の例では、Visual Basic の When 式による filter 句が使用されています (他の言語の例では省略されています)。

このコードは、MethodBody クラスのトピックで取り上げているコード例の一部分です。

Imports System
Imports System.Reflection

Public Class Example

    Public Shared Sub Main()

        ' Demonstrate the effect of the Visual Basic When keyword, which
        ' generates a Filter clause in the Try block.
        Dim e As New Example()
        Console.WriteLine()
        e.MethodBodyExample("String argument")
        e.MethodBodyExample(Nothing)

        ' Get method body information.
        Dim mi As MethodInfo = _
            GetType(Example).GetMethod("MethodBodyExample")
        Dim mb As MethodBody = mi.GetMethodBody()
        Console.WriteLine(vbCrLf & "Method: {0}",
 mi)

        ' Display the general information included in the 
        ' MethodBody object.
        Console.WriteLine("    Local variables are initialized:
 {0}", _
            mb.InitLocals)
        Console.WriteLine("    Maximum number of items on the
 operand stack: {0}", _
            mb.MaxStackSize)
<br /><span space="preserve">...</span><br
 />
        ' Display exception handling clauses.
        Console.WriteLine()
        For Each ehc As
 ExceptionHandlingClause In mb.ExceptionHandlingClauses
            Console.WriteLine(ehc.Flags.ToString())

            ' The FilterOffset property is meaningful only for Filter
            ' clauses. The CatchType property is not meaningful for
 
            ' Filter or Finally clauses. 
            Select Case ehc.Flags
                Case ExceptionHandlingClauseOptions.Filter
                    Console.WriteLine("        Filter Offset:
 {0}", _
                        ehc.FilterOffset)
                Case ExceptionHandlingClauseOptions.Finally
                Case Else
                    Console.WriteLine("    Type of exception:
 {0}", _
                        ehc.CatchType)
            End Select

            Console.WriteLine("       Handler Length: {0}",
 ehc.HandlerLength)
            Console.WriteLine("       Handler Offset: {0}",
 ehc.HandlerOffset)
            Console.WriteLine("     Try Block Length: {0}",
 ehc.TryLength)
            Console.WriteLine("     Try Block Offset: {0}",
 ehc.TryOffset)
        Next
<br /><span space="preserve">...</span><br
 />    End Sub

    ' This test method is executed at the beginning of Main, to show
    ' how the Filter clause works. The Filter clause is generated by
 
    ' a Visual Basic When expression. If arg is Nothing, this method
    ' throws ArgumentNullException, which is caught by the filter
    ' clause. If arg is a string, the method throws ArgumentException
,
    ' which does not match the filter clause.
    '
    ' Sub Main also contains code to analyze this method, using 
    ' the properties and methods of the MethodBody class.
    Public Sub MethodBodyExample(ByVal
 arg As Object)

        ' Define some local variables. In addition to these variables
,
        ' the local variable list includes the variables scoped to 
        ' the catch clauses.
        Dim var1 As Integer
 = 42
        Dim var2 As String
 = "Forty-two"

        Try
            ' Depending on the input value, throw an ArgumentException
 or 
            ' an ArgumentNullException to test the Catch clauses.
            '
            If arg Is Nothing
 Then
                Throw New ArgumentNullException("The
 argument cannot be Nothing.")
            End If
            If arg.GetType() Is GetType(String)
 Then
                Throw New ArgumentException("The
 argument cannot be a string.")
            End If
        
        ' The When expression makes this a filter clause. The expression
 
        ' selects only exceptions that derive from the ArgumentException
        ' class. Other exceptions, including ArgumentException itself,
 
        ' are not handled by this filter clause.
        Catch ex As ArgumentException _
            When ex.GetType().IsSubclassOf(GetType(ArgumentException))

            Console.WriteLine("Filter clause caught: {0}",
 ex.GetType())
        
        ' This catch clause handles the ArgumentException class, and
        ' any other class derived from Exception.
        Catch ex As Exception
            Console.WriteLine("Ordinary exception-handling clause
 caught: {0}", _
                ex.GetType())

        Finally
            var1 = 3033
            var2 = "Another string."
        End Try
    End Sub
End Class

' This code example produces output similar to the following:
'
'Ordinary exception-handling clause caught: System.ArgumentException
'Filter clause caught: System.ArgumentNullException
'
'Method: Void MethodBodyExample(System.Object)
'    Local variables are initialized: True
'    Maximum number of items on the operand stack: 3
<br /><span space="preserve">...</span><br
 />'
'Filter
'        Filter Offset: 0
'       Handler Length: 19
'       Handler Offset: 99
'     Try Block Length: 45
'     Try Block Offset: 9
'Clause
'    Type of exception: System.Exception
'       Handler Length: 25
'       Handler Offset: 118
'     Try Block Length: 45
'     Try Block Offset: 9
'Finally
'       Handler Length: 13
'       Handler Offset: 153
'     Try Block Length: 144
'     Try Block Offset: 9
using System;
using System.Reflection;

public class Example
{
    public static void Main()
    {
        // Get method body information.
        MethodInfo mi = typeof(Example).GetMethod("MethodBodyExample");
        MethodBody mb = mi.GetMethodBody();
        Console.WriteLine("\r\nMethod: {0}", mi);

        // Display the general information included in the 
        // MethodBody object.
        Console.WriteLine("    Local variables are initialized: {0}", 
            mb.InitLocals);
        Console.WriteLine("    Maximum number of items on the operand stack:
 {0}", 
            mb.MaxStackSize);
<br /><span space="preserve">...</span><br />
        // Display exception handling clauses.
        Console.WriteLine();
        foreach (ExceptionHandlingClause ehc in
 mb.ExceptionHandlingClauses)
        {
            Console.WriteLine(ehc.Flags.ToString());

            // The FilterOffset property is meaningful only for Filter
            // clauses. The CatchType property is not meaningful for
 
            // Filter or Finally clauses. 
            switch (ehc.Flags)
            {
                case ExceptionHandlingClauseOptions.Filter:
                    Console.WriteLine("        Filter Offset: {0}", 
                        ehc.FilterOffset);
                    break;
                case ExceptionHandlingClauseOptions.Finally:
                    break;
                default:
                    Console.WriteLine("    Type of exception: {0}", 
                        ehc.CatchType);
                    break;
            }

            Console.WriteLine("       Handler Length: {0}", ehc.HandlerLength);
            Console.WriteLine("       Handler Offset: {0}", ehc.HandlerOffset);
            Console.WriteLine("     Try Block Length: {0}", ehc.TryLength);
            Console.WriteLine("     Try Block Offset: {0}", ehc.TryOffset);
        }
<br /><span space="preserve">...</span><br /> 
   }

    // The Main method contains code to analyze this method, using
    // the properties and methods of the MethodBody class.
    public void MethodBodyExample(object arg)
    {
        // Define some local variables. In addition to these variables
,
        // the local variable list includes the variables scoped to
 
        // the catch clauses.
        int var1 = 42;
        string var2 = "Forty-two";

        try
        {
            // Depending on the input value, throw an ArgumentException
 or 
            // an ArgumentNullException to test the Catch clauses.
            if (arg == null)
            {
                throw new ArgumentNullException("The argument
 cannot be null.");
            }
            if (arg.GetType() == typeof(string))
            {
                throw new ArgumentException("The argument
 cannot be a string.");
            }        
        }

        // There is no Filter clause in this code example. See the Visual
 
        // Basic code for an example of a Filter clause.

        // This catch clause handles the ArgumentException class, and
        // any other class derived from Exception.
        catch(Exception ex)
        {
            Console.WriteLine("Ordinary exception-handling clause caught: {0}",
 
                ex.GetType());
        }        
        finally
        {
            var1 = 3033;
            var2 = "Another string.";
        }
    }
}

// This code example produces output similar to the following:
//
//Method: Void MethodBodyExample(System.Object)
//    Local variables are initialized: True
//    Maximum number of items on the operand stack: 2
<br /><span space="preserve">...</span><br />//
//Clause
//    Type of exception: System.Exception
//       Handler Length: 21
//       Handler Offset: 70
//     Try Block Length: 61
//     Try Block Offset: 9
//Finally
//       Handler Length: 14
//       Handler Offset: 94
//     Try Block Length: 85
//     Try Block Offset: 9
#using <System.dll>

using namespace System;
using namespace System::Reflection;

public ref class Example
{
    // The Main method contains code to analyze this method, using
    // the properties and methods of the MethodBody class.
public:
    void MethodBodyExample(Object^ arg)
    {
        // Define some local variables. In addition to these variables
,
        // the local variable list includes the variables scoped to
 
        // the catch clauses.
        int var1 = 42;
        String^ var2 = "Forty-two";

        try
        {
            // Depending on the input value, throw an ArgumentException
 or 
            // an ArgumentNullException to test the Catch clauses.
            if (arg == nullptr)
            {
                throw gcnew ArgumentNullException("The argument cannot "
 +
                    "be null.");
            }
            if (arg->GetType() == String::typeid)
            {
                throw gcnew ArgumentException("The argument cannot " +
 
                    "be a string.");
            }        
        }

        // There is no Filter clause in this code example. See the Visual
 
        // Basic code for an example of a Filter clause.

        // This catch clause handles the ArgumentException class, and
        // any other class derived from Exception.
        catch (ArgumentException^ ex)
        {
            Console::WriteLine("Ordinary exception-handling clause caught:"
 +
                " {0}", ex->GetType());
        }        
        finally
        {
            var1 = 3033;
            var2 = "Another string.";
        }
    }
};

int main()
{ 
    // Get method body information.
    MethodInfo^ mi = 
        Example::typeid->GetMethod("MethodBodyExample");

    MethodBody^ mb = mi->GetMethodBody();
    Console::WriteLine("\r\nMethod: {0}", mi);

    // Display the general information included in the 
    // MethodBody object.
    Console::WriteLine("    Local variables are initialized: {0}", 
        mb->InitLocals);
    Console::WriteLine("    Maximum number of items on the operand " +
        "stack: {0}", mb->MaxStackSize);
<br /><span space="preserve">...</span><br />
    // Display exception handling clauses.
    Console::WriteLine();
    for each(ExceptionHandlingClause^ exhc in
 mb->ExceptionHandlingClauses)
    {
        Console::WriteLine(exhc->Flags.ToString());

        // The FilterOffset property is meaningful only for Filter
        // clauses. The CatchType property is not meaningful for 
        // Filter or Finally clauses. 
        switch(exhc->Flags)
        {
        case ExceptionHandlingClauseOptions::Filter:
            Console::WriteLine("        Filter Offset: {0}", 
                exhc->FilterOffset);
            break;
        case ExceptionHandlingClauseOptions::Finally:
            break;
        default:
            Console::WriteLine("    Type of exception: {0}", 
                exhc->CatchType);
            break;
        }

        Console::WriteLine("       Handler Length: {0}",
            exhc->HandlerLength);
        Console::WriteLine("       Handler Offset: {0}", 
            exhc->HandlerOffset);
        Console::WriteLine("     Try Block Length: {0}", exhc->TryLength);
        Console::WriteLine("     Try Block Offset: {0}", exhc->TryOffset);
    }
<br /><span space="preserve">...</span><br /> 
   // The Main method contains code to analyze this method, using
    // the properties and methods of the MethodBody class.
public:
    void MethodBodyExample(Object^ arg)
    {
        // Define some local variables. In addition to these variables
,
        // the local variable list includes the variables scoped to
 
        // the catch clauses.
        int var1 = 42;
        String^ var2 = "Forty-two";

        try
        {
            // Depending on the input value, throw an ArgumentException
 or 
            // an ArgumentNullException to test the Catch clauses.
            if (arg == nullptr)
            {
                throw gcnew ArgumentNullException("The argument cannot "
 +
                    "be null.");
            }
            if (arg->GetType() == String::typeid)
            {
                throw gcnew ArgumentException("The argument cannot " +
 
                    "be a string.");
            }        
        }

        // There is no Filter clause in this code example. See the Visual
 
        // Basic code for an example of a Filter clause.

        // This catch clause handles the ArgumentException class, and
        // any other class derived from Exception.
        catch (ArgumentException^ ex)
        {
            Console::WriteLine("Ordinary exception-handling clause caught:"
 +
                " {0}", ex->GetType());
        }        
        finally
        {
            var1 = 3033;
            var2 = "Another string.";
        }
    }
継承階層継承階層
System.Object
  System.Reflection.ExceptionHandlingClause
スレッド セーフスレッド セーフ
この型の public static (Visual Basic では Shared) メンバはすべて、スレッド セーフです。インスタンス メンバの場合は、スレッド セーフであるとは限りません。
プラットフォームプラットフォーム
バージョン情報バージョン情報
参照参照
関連項目
ExceptionHandlingClause メンバ
System.Reflection 名前空間
MethodBody
MethodBody.ExceptionHandlingClauses
ExceptionHandlingClauseOptions

ExceptionHandlingClause プロパティ


パブリック プロパティパブリック プロパティ

参照参照

関連項目

ExceptionHandlingClause クラス
System.Reflection 名前空間
MethodBody
MethodBody.ExceptionHandlingClauses
ExceptionHandlingClauseOptions

ExceptionHandlingClause メソッド


ExceptionHandlingClause メンバ

構造化例外処理ブロック内の句を表します。

ExceptionHandlingClause データ型で公開されるメンバを以下の表に示します。


パブリック プロパティパブリック プロパティ
パブリック メソッドパブリック メソッド
参照参照

関連項目

ExceptionHandlingClause クラス
System.Reflection 名前空間
MethodBody
MethodBody.ExceptionHandlingClauses
ExceptionHandlingClauseOptions



英和和英テキスト翻訳

英語⇒日本語日本語⇒英語

辞書ショートカット

すべての辞書の索引

「ExceptionHandlingClause」の関連用語

ExceptionHandlingClauseのお隣キーワード
検索ランキング

   

英語⇒日本語
日本語⇒英語
   



ExceptionHandlingClauseのページの著作権

   
日本マイクロソフト株式会社日本マイクロソフト株式会社
© 2026 Microsoft.All rights reserved.

©2026 GRAS Group, Inc.RSS