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DescriptionAttribute Class

Definition

Specifies a description for a property or event.

public ref class DescriptionAttribute : Attribute
[System.AttributeUsage(System.AttributeTargets.All)]
public class DescriptionAttribute : Attribute
public class DescriptionAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.All)>]
type DescriptionAttribute = class
    inherit Attribute
type DescriptionAttribute = class
    inherit Attribute
Public Class DescriptionAttribute
Inherits Attribute
Inheritance
DescriptionAttribute
Derived
Attributes

Examples

The following example creates the MyImage property. The property has two attributes, a DescriptionAttribute and a CategoryAttribute.

public:
   property Image^ MyImage 
   {
      [Description("The image associated with the control"),Category("Appearance")]
      Image^ get()
      {
         // Insert code here.
         return image1;
      }

      void set( Image^ value )
      {
         // Insert code here.
      }
   }
[Description("The image associated with the control"),Category("Appearance")] 
 public Image MyImage {
    get {
       // Insert code here.
       return image1;
    }
    set {
       // Insert code here.
    }
 }
<Description("The image associated with the control"), _
    Category("Appearance")> _
Public Property MyImage() As Image
    Get
        ' Insert code here.
        Return image1
    End Get
    Set
        ' Insert code here.
    End Set 
End Property

The next example gets the description of MyImage. First the code gets a PropertyDescriptorCollection with all the properties for the object. Next it indexes into the PropertyDescriptorCollection to get MyImage. Then it returns the attributes for this property and saves them in the attributes variable.

The example then prints the description by retrieving DescriptionAttribute from the AttributeCollection, and writing it to the console screen.

// Gets the attributes for the property.
AttributeCollection^ attributes = TypeDescriptor::GetProperties( this )[ "MyImage" ]->Attributes;

/* Prints the description by retrieving the DescriptionAttribute 
      * from the AttributeCollection. */
DescriptionAttribute^ myAttribute = dynamic_cast<DescriptionAttribute^>(attributes[ DescriptionAttribute::typeid ]);
Console::WriteLine( myAttribute->Description );
// Gets the attributes for the property.
 AttributeCollection attributes = 
    TypeDescriptor.GetProperties(this)["MyImage"].Attributes;
 
 /* Prints the description by retrieving the DescriptionAttribute 
  * from the AttributeCollection. */
 DescriptionAttribute myAttribute = 
    (DescriptionAttribute)attributes[typeof(DescriptionAttribute)];
 Console.WriteLine(myAttribute.Description);
' Gets the attributes for the property.
Dim attributes As AttributeCollection = _
    TypeDescriptor.GetProperties(Me)("MyImage").Attributes

' Prints the description by retrieving the DescriptionAttribute
' from the AttributeCollection. 
Dim myAttribute As DescriptionAttribute = _
    CType(attributes(GetType(DescriptionAttribute)), DescriptionAttribute)
Console.WriteLine(myAttribute.Description)

Remarks

A visual designer can display the specified description when referencing the component member, such as in a Properties window. Call Description to access the value of this attribute.

For more information, see Attributes.

Constructors

DescriptionAttribute()

Initializes a new instance of the DescriptionAttribute class with no parameters.

DescriptionAttribute(String)

Initializes a new instance of the DescriptionAttribute class with a description.

Fields

Default

Specifies the default value for the DescriptionAttribute, which is an empty string (""). This static field is read-only.

Properties

Description

Gets the description stored in this attribute.

DescriptionValue

Gets or sets the string stored as the description.

TypeId

When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Methods

Equals(Object)

Returns whether the value of the given object is equal to the current DescriptionAttribute.

GetHashCode()

Returns the hash code for this instance.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute()

Returns a value indicating whether this is the default DescriptionAttribute instance.

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)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.

(Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.

(Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).

(Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.

(Inherited from Attribute)

Applies to

See also