DispIdAttribute Class

Definition

Namespace:

System.Runtime.InteropServices

Assembly:

System.Runtime.InteropServices.dll

Source:

DispIdAttribute.cs

Specifies the COM dispatch identifier (DISPID) of a method, field, or property.

public ref class DispIdAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Event | System.AttributeTargets.Field | System.AttributeTargets.Method | System.AttributeTargets.Property, Inherited=false)]
public sealed class DispIdAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Event | System.AttributeTargets.Field | System.AttributeTargets.Method | System.AttributeTargets.Property, Inherited=false)>]
type DispIdAttribute = class
    inherit Attribute

Public NotInheritable Class DispIdAttribute
Inherits Attribute

Inheritance

Object

Attribute

DispIdAttribute

Attributes

AttributeUsageAttribute

Examples

The following example demonstrates how explicit DISPIDs can be assigned to members of a class.

using namespace System::Runtime::InteropServices;
public ref class MyClass
{
public:
   MyClass(){}


   [DispId(8)]
   void MyMethod(){}

   int MyOtherMethod()
   {
      return 0;
   }


   [DispId(9)]
   bool MyField;
};

using System.Runtime.InteropServices;

public class MyClass
{
   public MyClass() {}

   [DispId(8)]
   public void MyMethod() {}

   public int MyOtherMethod() {
      return 0;
   }

   [DispId(9)]
   public bool MyField;
}

Imports System.Runtime.InteropServices

Class SampleClass
    
    Public Sub New()
        'Insert code here.
    End Sub
    
    <DispIdAttribute(8)> _ 
    Public Sub MyMethod()
        'Insert code here.
    End Sub    
    
    Public Function MyOtherMethod() As Integer
        'Insert code here.
        Return 0
    End Function
    
    <DispId(9)> _
    Public MyField As Boolean
End Class

Remarks

You can apply this attribute to methods, fields, or properties.

This attribute contains the DISPID for the method, field, or property it describes. Unique DISPIDs are typically assigned by the common language runtime, but you can use this attribute to assign a specific DISPID to a method. When importing a type library, this attribute is applied to all methods with assigned DISPIDs. This ensures that any managed implementation of the same method retains the same DISPID if exposed to COM.

See DISPID Constants for a list of commonly used DISPID values.

Constructors

DispIdAttribute(Int32)

Initializes a new instance of the DispIdAttribute class with the specified DISPID.

Properties

TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)
Value	Gets the DISPID for the member.

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsDefaultAttribute()	When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute)
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)