MethodBuilder.MakeGenericMethod Method (Type[])


Returns a generic method constructed from the current generic method definition using the specified generic type arguments.

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

public override MethodInfo MakeGenericMethod(
	params Type[] typeArguments


Type: System.Type[]

An array of Type objects that represent the type arguments for the generic method.

Return Value

Type: System.Reflection.MethodInfo

A MethodInfo representing the generic method constructed from the current generic method definition using the specified generic type arguments.

When you are emitting dynamic code, you might need to emit a call to a method constructed from the generic method definition represented by a MethodBuilder, before the enclosing type has been completed. You can use the MakeGenericMethod method to create a MethodInfo for such a constructed method, and use the MethodInfo in the emitted call.

The following code example creates a constructed method from an incomplete generic method definition in an incomplete type.

The example creates a transient assembly and module with a single type, adds a method M, and makes the method generic by adding a type parameter T using the DefineGenericParameters method. The type parameter is used as the type of the method's parameter, and also as its return type. The generic method definition is not given a body, and the enclosing type is not completed. The MakeGenericMethod method is then used to make the constructed method M<String> (M(Of String) in Visual Basic). The example code has no output, because the subclass of MethodInfo returned by the MakeGenericMethod method does not allow reflection over its parameters.


For another code example that uses MakeGenericMethod, see DefineGenericParameters. MakeGenericMethod is also used extensively when emitting code that uses generic types. See How to: Define a Generic Method with Reflection Emit.

using System;
using System.Reflection;
using System.Reflection.Emit;

class Example
    public static void Main()
        // Define a transient dynamic assembly (only to run, not
        // to save) with one module and a type "Test".
        AssemblyName aName = new AssemblyName("MyDynamic");
        AssemblyBuilder ab = 
        ModuleBuilder mb = ab.DefineDynamicModule(aName.Name);
        TypeBuilder tb = mb.DefineType("Test");

        // Add a public static method "M" to Test, and make it a
        // generic method with one type parameter named "T").
        MethodBuilder meb = tb.DefineMethod("M", 
            MethodAttributes.Public | MethodAttributes.Static);
        GenericTypeParameterBuilder[] typeParams = 
            meb.DefineGenericParameters(new string[] { "T" });

        // Give the method one parameter, of type T, and a 
        // return type of T.

        // Create a MethodInfo for M<string>, which can be used in
        // emitted code. This is possible even though the method
        // does not yet have a body, and the enclosing type is not
        // created.
        MethodInfo mi = meb.MakeGenericMethod(typeof(string));
        // Note that this is actually a subclass of MethodInfo, 
        // which has rather limited capabilities -- for
        // example, you cannot reflect on its parameters.

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