MethodBase.GetMethodBody Método

Definición

Cuando se reemplaza en una clase derivada, obtiene un objeto MethodBody que proporciona el acceso a la secuencia de MSIL, las variables locales y las excepciones del método actual.When overridden in a derived class, gets a MethodBody object that provides access to the MSIL stream, local variables, and exceptions for the current method.

public:
 virtual System::Reflection::MethodBody ^ GetMethodBody();
public virtual System.Reflection.MethodBody GetMethodBody ();
abstract member GetMethodBody : unit -> System.Reflection.MethodBody
override this.GetMethodBody : unit -> System.Reflection.MethodBody
Public Overridable Function GetMethodBody () As MethodBody

Devoluciones

Un objeto MethodBody que proporciona el acceso a la secuencia de MSIL, las variables locales y las excepciones del método actual.A MethodBody object that provides access to the MSIL stream, local variables, and exceptions for the current method.

Excepciones

Este método no es válido a menos que se reemplace en una clase derivada.This method is invalid unless overridden in a derived class.

Ejemplos

En el ejemplo de código siguiente se define un MethodBodyExample método de prueba denominado y se muestra su información de variable local y las cláusulas de control de excepciones.The following code example defines a test method named MethodBodyExample and displays its local variable information and exception-handling clauses. El MethodBase.GetMethodBody método se utiliza para obtener un MethodBody objeto para el método de prueba.The MethodBase.GetMethodBody method is used to obtain a MethodBody object for the test method.

La LocalVariables propiedad se utiliza para obtener una lista de LocalVariableInfo objetos y mostrar sus tipos y el orden de los índices.The LocalVariables property is used to obtain a list of LocalVariableInfo objects and display their types and index order. La ExceptionHandlingClauses propiedad se utiliza para obtener una lista de las cláusulas de control de excepciones.The ExceptionHandlingClauses property is used to obtain a list of exception-handling clauses.

Nota

No todos los idiomas del equipo ExceptionHandlingClauseOptions.Filter pueden generar cláusulas.Not all computer languages can generate ExceptionHandlingClauseOptions.Filter clauses. En el ejemplo Visual Basic se muestra una cláusula de filtro mediante When una expresión Visual Basic, que se omite en los ejemplos de otros lenguajes.The Visual Basic example shows a filter clause, using a Visual Basic When expression, which is omitted from the examples for other languages.

#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);

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

    // 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);
    }
}

//This code example produces output similar to the following:
//
//Method: Void MethodBodyExample(System.Object)
//    Local variables are initialized: False
//    Maximum number of items on the operand stack: 4
//
//Local variable: System.ArgumentException (0)
//Local variable: System.String (1)
//Local variable: System.Int32 (2)
//Clause
//    Type of exception: System.ArgumentException
//       Handler Length: 29
//       Handler Offset: 78
//     Try Block Length: 65
//     Try Block Offset: 13
//Finally
//       Handler Length: 13
//       Handler Offset: 113
//     Try Block Length: 100
//     Try Block Offset: 13
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);

        // 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 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);
        }
    }

    // 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
//
//Local variable: System.Int32 (0)
//Local variable: System.String (1)
//Local variable: System.Exception (2)
//Local variable: System.Boolean (3)
//
//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
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()
        For Each lvi As LocalVariableInfo In mb.LocalVariables
            Console.WriteLine("Local variable: {0}", lvi)
        Next

        ' 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
    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.ArgumentException (2)
'Local variable: System.Exception (3)
'
'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

Comentarios

No es necesario invalidar el GetMethodBody para poder usarlo.You do not have to override the GetMethodBody in order to use it. Puede llamar al GetMethodBody método en MethodInfo los objetos ConstructorInfo y, porque el método se invalida en las versiones en tiempo de ejecución de estas clases.You can call the GetMethodBody method on MethodInfo and ConstructorInfo objects, because the method is overridden in the runtime versions of these classes. Por ejemplo, la versión en tiempo de MethodInfo ejecución de la clase se MethodInfo deriva de la clase, que a su vez MethodBase se deriva de la clase.For example, the runtime version of the MethodInfo class derives from the MethodInfo class, which in turn derives from the MethodBase class.

Seguridad

ReflectionPermission
para el acceso a los metadatos de los miembros.for the access to metadata for members. Valor de permiso:MemberAccessPermission value: MemberAccess

Se aplica a