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MethodBase.GetMethodBody Method

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.

Namespace:  System.Reflection
Assembly:  mscorlib (in mscorlib.dll)

[ReflectionPermissionAttribute(SecurityAction.Demand, Flags = ReflectionPermissionFlag.MemberAccess)]
public virtual MethodBody GetMethodBody()

Return Value

Type: System.Reflection.MethodBody
A MethodBody object that provides access to the MSIL stream, local variables, and exceptions for the current method.

ExceptionCondition
InvalidOperationException

This method is invalid unless overridden in a derived class.

You do not have to override the GetMethodBody in order to use it. You can call the GetMethodBody method on MethodInfo and ConstructorInfo objects, because the method is overridden in the runtime versions of these classes. For example, the runtime version of the MethodInfo class derives from the MethodInfo class, which in turn derives from the MethodBase class.

The following code example defines a test method named MethodBodyExample and displays its local variable information and exception-handling clauses. The MethodBase.GetMethodBody method is used to obtain a MethodBody object for the test method.

The LocalVariables property is used to obtain a list of LocalVariableInfo objects and display their types and index order. The ExceptionHandlingClauses property is used to obtain a list of exception-handling clauses.

NoteNote

Not all computer languages can generate ExceptionHandlingClauseOptions.Filter clauses. 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;
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

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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