TypeBuilder.DefineDefaultConstructor(MethodAttributes) Method

Definition

Namespace:

System.Reflection.Emit

Assemblies:

netstandard.dll, System.Reflection.Emit.dll

Source:

TypeBuilder.cs

Defines the parameterless constructor. The constructor defined here will simply call the parameterless constructor of the parent.

C#

public System.Reflection.Emit.ConstructorBuilder DefineDefaultConstructor(System.Reflection.MethodAttributes attributes);

Parameters

attributes

MethodAttributes

A MethodAttributes object representing the attributes to be applied to the constructor.

Returns

ConstructorBuilder

Returns the constructor.

Exceptions

NotSupportedException

The parent type (base type) does not have a parameterless constructor.

InvalidOperationException

The type was previously created using CreateType().

-or-

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

Examples

The following code sample demonstrates the use of DefineConstructor to set a constructor's particular signature and attributes on a dynamic type and return a corresponding ConstructorBuilder for MSIL population.

C#

// Define the constructor.
Type[] constructorArgs = { typeof(String) };
ConstructorBuilder myConstructorBuilder =
   helloWorldTypeBuilder.DefineConstructor(MethodAttributes.Public,
                      CallingConventions.Standard, constructorArgs);
// Generate IL for the method. The constructor stores its argument in the private field.
ILGenerator myConstructorIL = myConstructorBuilder.GetILGenerator();
myConstructorIL.Emit(OpCodes.Ldarg_0);
myConstructorIL.Emit(OpCodes.Ldarg_1);
myConstructorIL.Emit(OpCodes.Stfld, myGreetingField);
myConstructorIL.Emit(OpCodes.Ret);

Remarks

Because the parameterless constructor is automatically defined, it is necessary to call this method only in the following situations:

• You have defined another constructor and you also want a parameterless constructor that simply calls the base class constructor.

• You want to set the attributes on the parameterless constructor to something other than PrivateScope, Public, HideBySig, SpecialName, and RTSpecialName.

Applies to