Information
Switch
Switch
The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

Attribute::IsDefined Method (ParameterInfo^, Type^)

.NET Framework (current version)
 

Determines whether any custom attributes are applied to a method parameter. Parameters specify the method parameter, and the type of the custom attribute to search for.

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

C#
C++
F#
VB
Copy 
public:
static bool IsDefined(
	ParameterInfo^ element,
	Type^ attributeType
)

Parameters

element
Type: System.Reflection::ParameterInfo^

An object derived from the ParameterInfo class that describes a parameter of a member of a class.

attributeType
Type: System::Type^

The type, or a base type, of the custom attribute to search for.

Return Value

Type: System::Boolean

true if a custom attribute of type attributeType is applied to element; otherwise, false.

Exception Condition
ArgumentNullException

element or attributeType is null.

ArgumentException

attributeType is not derived from Attribute.

The ancestors of element are searched for custom attributes.

The following code example illustrates the use of IsDefined, taking a ParameterInfo as a parameter.

C#
C++
VB
Copy 
using namespace System;
using namespace System::Reflection;

namespace IsDef5CS
{
   public ref class TestClass
   {
   public:

      // Assign a ParamArray attribute to the parameter using the keyword.
      void Method1(... array<String^>^args ){}

   };

   ref class DemoClass
   {
   public:
      static void Main()
      {

         // Get the class type to access its metadata.
         Type^ clsType = TestClass::typeid;

         // Get the MethodInfo object for Method1.
         MethodInfo^ mInfo = clsType->GetMethod( "Method1" );

         // Get the ParameterInfo array for the method parameters.
         array<ParameterInfo^>^pInfo = mInfo->GetParameters();
         if ( pInfo != nullptr )
         {

            // See if the ParamArray attribute is defined.
            bool isDef = Attribute::IsDefined( pInfo[ 0 ], ParamArrayAttribute::typeid );

            // Display the result.
            Console::WriteLine( "The ParamArray attribute {0} defined for "
            "parameter {1} of method {2}.", isDef ? (String^)"is" : "is not", pInfo[ 0 ]->Name, mInfo->Name );
         }
         else
                  Console::WriteLine( "The parameters information could "
         "not be retrieved for method {0}.", mInfo->Name );
      }

   };

}

/*
 * Output:
 * The ParamArray attribute is defined for parameter args of method Method1.
 */

.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Return to top
Show: