TypeBuilder.MakeGenericType(Type[]) Method

Definition

Namespace:

System.Reflection.Emit

Assembly:

System.Reflection.Emit.dll

Source:

TypeBuilder.cs

Substitutes the elements of an array of types for the type parameters of the current generic type definition, and returns the resulting constructed type.

public:
 override Type ^ MakeGenericType(... cli::array <Type ^> ^ typeArguments);

public override Type MakeGenericType (params Type[] typeArguments);

override this.MakeGenericType : Type[] -> Type

Public Overrides Function MakeGenericType (ParamArray typeArguments As Type()) As Type

Parameters

typeArguments

Type[]

An array of types to be substituted for the type parameters of the current generic type definition.

Returns

Type

A Type representing the constructed type formed by substituting the elements of typeArguments for the type parameters of the current generic type.

Exceptions

InvalidOperationException

The current type does not represent the definition of a generic type. That is, IsGenericTypeDefinition returns false.

ArgumentNullException

typeArguments is null.

-or-

Any element of typeArguments is null.

ArgumentException

The Module property of any element of typeArguments is null.

-or-

The Assembly property of the module of any element of typeArguments is null.

Remarks

Use this method when your emitted code requires a type constructed from the current generic type definition. It is not necessary to call the CreateType method before calling the MakeGenericType method on a TypeBuilder that represents a generic type definition. If the current TypeBuilder does not represent the definition of a generic type, an InvalidOperationException is thrown.

The object returned by this method functions as a placeholder for a constructed generic type in your emitted code. It is an instance of a class derived from Type that has limited capabilities. In particular:

• To get methods, fields, and constructors for these constructed generic types, use the GetMethod(Type, MethodInfo), GetField(Type, FieldInfo), and GetConstructor(Type, ConstructorInfo) method overloads.

• Two instances that represent the same constructed type do not compare as equal. For example, in the following code t1.Equals(t2) returns false:

Type^ t1 = tbldr->MakeGenericType(String::typeid);
Type^ t2 = tbldr->MakeGenericType(String::typeid);
bool result = t1->Equals(t2);

Type t1 = tbldr.MakeGenericType(typeof(string));
Type t2 = tbldr.MakeGenericType(typeof(string));
bool result = t1.Equals(t2);

Dim t1 As Type = tbldr.MakeGenericType(GetType(String))
Dim t2 As Type = tbldr.MakeGenericType(GetType(String))
Dim result As Boolean = t1.Equals(t2)