TypeBuilder.DefineMethod Method (String, MethodAttributes)


Adds a new method to the type, with the specified name and method attributes.

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

public MethodBuilder DefineMethod(
	string name,
	MethodAttributes attributes


Type: System.String

The name of the method. name cannot contain embedded nulls.

Type: System.Reflection.MethodAttributes

The attributes of the method.

Return Value

Type: System.Reflection.Emit.MethodBuilder

A MethodBuilder representing the newly defined method.

Exception Condition

The length of name is zero.


The type of the parent of this method is an interface, and this method is not virtual (Overridable in Visual Basic).


name is null.


The type was previously created using CreateType.


For the current dynamic type, the IsGenericType property is true, but the IsGenericTypeDefinition property is false.

Use this method overload when you do not know the method signature at the time you define the method. For example, the parameter types and return type of a generic method might be specified by the method's generic type parameters, which must be defined after the method has been added to the type. The parameters and return type of the method can be set later using the MethodBuilder.SetSignature method.

This method overload defines a method with CallingConventions.Standard. If you need to define a method without a signature, with a different calling convention, use the DefineMethod(String, MethodAttributes, CallingConventions) method overload.

The following code example defines a generic method named DemoMethod whose parameter type and return type are specified by its generic type parameters. The method is defined without a signature, using the standard calling convention. The MethodBuilder.DefineGenericParameters method is used to make DemoMethod a generic method, and the newly defined type parameters are then used for the signature and return type.

This code example is part of a larger example provided for the DefineGenericParameters method.

// Define a Shared, Public method with standard calling
// conventions. Do not specify the parameter types or the
// return type, because type parameters will be used for 
// those types, and the type parameters have not been
// defined yet.
MethodBuilder demoMethod = demoType.DefineMethod(
    MethodAttributes.Public | MethodAttributes.Static
// Defining generic parameters for the method makes it a
// generic method. By convention, type parameters are 
// single alphabetic characters. T and U are used here.
string[] typeParamNames = {"T", "U"};
GenericTypeParameterBuilder[] typeParameters = 

// The second type parameter is constrained to be a 
// reference type.
// Set parameter types for the method. The method takes
// one parameter, and its type is specified by the first
// type parameter, T.
Type[] parms = {typeParameters[0]};

// Set the return type for the method. The return type is
// specified by the second type parameter, U.

.NET Framework
Available since 2.0
Available since 2.0
Return to top