LocalVariableInfo Klass

Definition

public ref class LocalVariableInfo

public class LocalVariableInfo

[System.Runtime.InteropServices.ComVisible(true)]
public class LocalVariableInfo

type LocalVariableInfo = class

[<System.Runtime.InteropServices.ComVisible(true)>]
type LocalVariableInfo = class

Public Class LocalVariableInfo

Arv

Object

LocalVariableInfo

Härledda

System.Reflection.Emit.LocalBuilder

Attribut

ComVisibleAttribute

Exempel

I följande exempel definieras en testmetod med namnet MethodBodyExampleoch dess lokala variabelinformation visas. Metoden GetMethodBody används för att hämta ett MethodBody objekt för testmetoden. Egenskapen LocalVariables används sedan för att hämta en lista över LocalVariableInfo objekt och för att visa deras typer och indexordning.

Det här kodexemplet är en del av ett större exempel för MethodBody klassen.

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);

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)

// Display information about the local variables in the
// method body.
Console.WriteLine();
foreach (LocalVariableInfo lvi in mb.LocalVariables)
{
    Console.WriteLine("Local variable: {0}", lvi);
}

' Display information about the local variables in the
' method body.
Console.WriteLine()
For Each lvi As LocalVariableInfo In mb.LocalVariables
    Console.WriteLine("Local variable: {0}", lvi)
Next

    }

    // 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.");
            }
        }

        // This filter clause selects only exceptions that derive
        // from the ArgumentException class.
        // Other exceptions, including ArgumentException itself,
        // are not handled by this filter clause.
        catch (ArgumentException ex) when (ex.GetType().IsSubclassOf(typeof(ArgumentException)))
        {
            Console.WriteLine("Filter clause caught: {0}", ex.GetType());
        }

        // 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

    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

//
//Local variable: System.Int32 (0)
//Local variable: System.String (1)
//Local variable: System.Exception (2)
//Local variable: System.Boolean (3)

'
'Local variable: System.Int32 (0)
'Local variable: System.String (1)
'Local variable: System.ArgumentException (2)
'Local variable: System.Exception (3)

Kommentarer

Om du vill hämta en lista över lokala variabler i en metod använder du MethodBody.LocalVariables egenskapen . MethodBase.GetMethodBody Använd metoden för att hämta MethodBody för ett MethodInfo objekt.

Se även

• LocalVariables