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Type.IsGenericParameter Property

  • Reference

Definition

Namespace:
System
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
Type.cs
Source:
Type.cs
Source:
Type.cs

Gets a value indicating whether the current Type represents a type parameter in the definition of a generic type or method.

public:
 abstract property bool IsGenericParameter { bool get(); };
public:
 virtual property bool IsGenericParameter { bool get(); };
public abstract bool IsGenericParameter { get; }
public virtual bool IsGenericParameter { get; }
member this.IsGenericParameter : bool
Public MustOverride ReadOnly Property IsGenericParameter As Boolean
Public Overridable ReadOnly Property IsGenericParameter As Boolean

Property Value

Boolean

true if the Type object represents a type parameter of a generic type definition or generic method definition; otherwise, false.

Examples

The following example uses the IsGenericParameter property to test for generic type parameters in a generic type.

if ( t->IsGenericType )
{
   
   // If this is a generic type, display the type arguments.
   //
   array<Type^>^typeArguments = t->GetGenericArguments();
   Console::WriteLine( L"\tList type arguments ({0}):",
      typeArguments->Length );
   System::Collections::IEnumerator^ myEnum =
      typeArguments->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Type^ tParam = safe_cast<Type^>(myEnum->Current);
      
      // If this is a type parameter, display its
      // position.
      //
      if ( tParam->IsGenericParameter )
      {
         Console::WriteLine(
            L"\t\t{0}\t(unassigned - parameter position {1})",
            tParam, tParam->GenericParameterPosition );
      }
      else
      {
         Console::WriteLine( L"\t\t{0}", tParam );
      }
   }
}

if (t.IsGenericType)
{
    // If this is a generic type, display the type arguments.
    //
    Type[] typeArguments = t.GetGenericArguments();

    Console.WriteLine("\tList type arguments ({0}):", 
        typeArguments.Length);

    foreach (Type tParam in typeArguments)
    {
        // If this is a type parameter, display its
        // position.
        //
        if (tParam.IsGenericParameter)
        {
            Console.WriteLine("\t\t{0}\t(unassigned - parameter position {1})",
                tParam,
                tParam.GenericParameterPosition);
        }
        else
        {
            Console.WriteLine("\t\t{0}", tParam);
        }
    }
}

if t.IsGenericType then
    // If this is a generic type, display the type arguments.
    let typeArguments = t.GetGenericArguments()

    printfn $"\tList type arguments ({typeArguments.Length}):" 

    for tParam in typeArguments do
        // If this is a type parameter, display its position.
        if tParam.IsGenericParameter then
            printfn $"\t\t{tParam}\t(unassigned - parameter position {tParam.GenericParameterPosition})"
        else
            printfn $"\t\t{tParam}"

If t.IsGenericType Then
    ' If this is a generic type, display the type arguments.
    '
    Dim typeArguments As Type() = t.GetGenericArguments()
    
    Console.WriteLine(vbTab & "List type arguments (" _
        & typeArguments.Length & "):")
    
    For Each tParam As Type In typeArguments
        ' If this is a type parameter, display its position.
        '
        If tParam.IsGenericParameter Then
            Console.WriteLine(vbTab & vbTab & tParam.ToString() _
                & vbTab & "(unassigned - parameter position " _
                & tParam.GenericParameterPosition & ")")
        Else
            Console.WriteLine(vbTab & vbTab & tParam.ToString())
        End If
    Next tParam
End If

Remarks

Type objects that represent generic type parameters can be obtained by calling the GetGenericArguments method of a Type object that represents a generic type definition, or the GetGenericArguments method of a MethodInfo object that represents a generic method definition.

  • For a generic type or method definition, the IsGenericParameter property returns true for every element of the resulting array.

  • For a closed constructed type or method, the IsGenericParameter property returns false for every element of the array returned by the GetGenericArguments method.

  • For an open constructed type or method, some elements of the array might be specific types and others might be type parameters. IsGenericParameter returns false for the types and true for the type parameters. The code example for the ContainsGenericParameters property demonstrates a generic class with a mixture of types and type parameters.

For a list of the invariant conditions for terms used in generic reflection, see the IsGenericType property remarks.

Applies to

See also