MethodBuilder.MakeGenericMethod(Type[]) Method

public:
 override System::Reflection::MethodInfo ^ MakeGenericMethod(... cli::array <Type ^> ^ typeArguments);

public override System.Reflection.MethodInfo MakeGenericMethod (params Type[] typeArguments);

override this.MakeGenericMethod : Type[] -> System.Reflection.MethodInfo

Public Overrides Function MakeGenericMethod (ParamArray typeArguments As Type()) As MethodInfo

Parameters

Returns

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

Examples

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.

using namespace System;
using namespace System::Reflection;
using namespace System::Reflection::Emit;

void main()
{
    // Define a transient dynamic assembly (only to run, not
    // to save) with one module and a type "Test".
    // 
    AssemblyName^ aName = gcnew AssemblyName("MyDynamic");
    AssemblyBuilder^ ab = 
        AppDomain::CurrentDomain->DefineDynamicAssembly(
            aName, 
            AssemblyBuilderAccess::Run);
    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);
    array<GenericTypeParameterBuilder^>^ typeParams = 
        meb->DefineGenericParameters(gcnew array<String^> { "T" });

    // Give the method one parameter, of type T, and a 
    // return type of T.
    meb->SetParameters(typeParams);
    meb->SetReturnType(typeParams[0]);

    // 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(String::typeid);
    // Note that this is actually a subclass of MethodInfo, 
    // which has rather limited capabilities -- for
    // example, you cannot reflect on its parameters.
}

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 =
            AppDomain.CurrentDomain.DefineDynamicAssembly(
                aName,
                AssemblyBuilderAccess.Run);
        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.
        meb.SetParameters(typeParams);
        meb.SetReturnType(typeParams[0]);

        // 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.
    }
}

Imports System.Reflection
Imports System.Reflection.Emit

Class Example

    Public Shared Sub Main()
    
        ' Define a transient dynamic assembly (only to run, not
        ' to save) with one module and a type "Test".
        ' 
        Dim aName As AssemblyName = New AssemblyName("MyDynamic")
        Dim ab As AssemblyBuilder = _
            AppDomain.CurrentDomain.DefineDynamicAssembly( _
                aName, _
                AssemblyBuilderAccess.Run)
        Dim mb As ModuleBuilder = ab.DefineDynamicModule(aName.Name)
        Dim tb As TypeBuilder = mb.DefineType("Test")

        ' Add a Public Shared method "M" to Test, and make it a
        ' generic method with one type parameter named "T").
        '
        Dim meb As MethodBuilder = tb.DefineMethod("M", _
            MethodAttributes.Public Or MethodAttributes.Static)
        Dim typeParams() As GenericTypeParameterBuilder = _
            meb.DefineGenericParameters(New String() { "T" })

        ' Give the method one parameter, of type T, and a 
        ' return type of T.
        meb.SetParameters(typeParams)
        meb.SetReturnType(typeParams(0))

        ' Create a MethodInfo for M(Of 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.
        Dim mi As MethodInfo = _
            meb.MakeGenericMethod(GetType(String))
        ' Note that this is actually a subclass of MethodInfo, 
        ' which has rather limited capabilities -- for
        ' example, you cannot reflect on its parameters.
    End Sub
End Class

Remarks

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.

Applies to

See also

• How to: Define a Generic Method with Reflection Emit