ModuleBuilder Class

Defines and represents a module. Get an instance of ModuleBuilder by calling DefineDynamicModule.

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

public class ModuleBuilder : Module, _ModuleBuilder
/** @attribute ComVisibleAttribute(true) */ 
/** @attribute ClassInterfaceAttribute(ClassInterfaceType.None) */ 
public class ModuleBuilder extends Module implements _ModuleBuilder
public class ModuleBuilder extends Module implements _ModuleBuilder


The HostProtectionAttribute attribute applied to this class has the following Resources property value: MayLeakOnAbort. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

The following code sample demonstrates the use of ModuleBuilder to create a dynamic module. Note that the ModuleBuilder is created by calling DefineDynamicModule in AssemblyBuilder, rather than through a constructor.

using System;
using System.Reflection;
using System.Reflection.Emit;
using System.Security.Permissions;

public class CodeGenerator
   AssemblyBuilder myAssemblyBuilder;
   public CodeGenerator()
      // Get the current application domain for the current thread.
      AppDomain myCurrentDomain = AppDomain.CurrentDomain;
      AssemblyName myAssemblyName = new AssemblyName();
      myAssemblyName.Name = "TempAssembly";

      // Define a dynamic assembly in the current application domain.
      myAssemblyBuilder = myCurrentDomain.DefineDynamicAssembly
                     (myAssemblyName, AssemblyBuilderAccess.Run);

      // Define a dynamic module in this assembly.
      ModuleBuilder myModuleBuilder = myAssemblyBuilder.

      // Define a runtime class with specified name and attributes.
      TypeBuilder myTypeBuilder = myModuleBuilder.DefineType

      // Add 'Greeting' field to the class, with the specified attribute and type.
      FieldBuilder greetingField = myTypeBuilder.DefineField("Greeting", 
                                                            typeof(String), FieldAttributes.Public);
      Type[] myMethodArgs = { typeof(String) };

      // Add 'MyMethod' method to the class, with the specified attribute and signature.
      MethodBuilder myMethod = myTypeBuilder.DefineMethod("MyMethod",
         MethodAttributes.Public, CallingConventions.Standard, null,myMethodArgs);

      ILGenerator methodIL = myMethod.GetILGenerator();
      methodIL.EmitWriteLine("In the method...");
      methodIL.Emit(OpCodes.Stfld, greetingField);
   public AssemblyBuilder MyAssembly
         return this.myAssemblyBuilder;
public class TestClass
   [PermissionSetAttribute(SecurityAction.Demand, Name="FullTrust")]
   public static void Main()
      CodeGenerator myCodeGenerator = new CodeGenerator();
      // Get the assembly builder for 'myCodeGenerator' object.
      AssemblyBuilder myAssemblyBuilder = myCodeGenerator.MyAssembly;
      // Get the module builder for the above assembly builder object .
      ModuleBuilder myModuleBuilder = myAssemblyBuilder.
      Console.WriteLine("The fully qualified name and path to this "
                               + "module is :" +myModuleBuilder.FullyQualifiedName);
      Type myType = myModuleBuilder.GetType("TempClass");
      MethodInfo myMethodInfo = 
       // Get the token used to identify the method within this module.
      MethodToken myMethodToken = 
      Console.WriteLine("Token used to identify the method of 'myType'"
                    + " within the module is {0:x}",myMethodToken.Token);
     object[] args={"Hello."};
     object myObject = Activator.CreateInstance(myType,null,null);


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

Community Additions