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BrowsableAttribute Class

Definition

Specifies whether a property or event should be displayed in a Properties window.

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

Examples

The following example marks a property as browsable.

public:
   [Browsable(true)]
   property int MyProperty 
   {
      int get()
      {
         // Insert code here.
         return 0;
      }
      void set( int value )
      {
         // Insert code here.
      }
   }
[Browsable(true)]
public int MyProperty
{
    get
    {
        // Insert code here.
        return 0;
    }
    set
    {
        // Insert code here.
    }
}

<Browsable(True)> _
Public Property MyProperty() As Integer
    Get
        ' Insert code here.
        Return 0
    End Get
    Set
        ' Insert code here.
    End Set 
End Property

The next example shows how to check the value of the BrowsableAttribute for MyProperty. First, the code gets a PropertyDescriptorCollection with all the properties for the object. Next, the code indexes into the PropertyDescriptorCollection to get MyProperty. Then it returns the attributes for this property and saves them in the attributes variable.

The example presents two different ways of checking the value of the BrowsableAttribute. In the second code fragment, the example calls the Equals method. In the last code fragment, the example uses the Browsable property to check the value.

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

// Checks to see if the value of the BrowsableAttribute is Yes.
if ( attributes[ BrowsableAttribute::typeid ]->Equals( BrowsableAttribute::Yes ) )
{
   
   // Insert code here.
}

// This is another way to see whether the property is browsable.
BrowsableAttribute^ myAttribute = dynamic_cast<BrowsableAttribute^>(attributes[ BrowsableAttribute::typeid ]);
if ( myAttribute->Browsable )
{
   // Insert code here.
}
// Gets the attributes for the property.
AttributeCollection attributes =
   TypeDescriptor.GetProperties(this)["MyProperty"].Attributes;

// Checks to see if the value of the BrowsableAttribute is Yes.
if (attributes[typeof(BrowsableAttribute)].Equals(BrowsableAttribute.Yes))
{
    // Insert code here.
}

// This is another way to see whether the property is browsable.
BrowsableAttribute myAttribute =
   (BrowsableAttribute)attributes[typeof(BrowsableAttribute)];
if (myAttribute.Browsable)
{
    // Insert code here.
}
' Gets the attributes for the property.
Dim attributes As AttributeCollection = _
    TypeDescriptor.GetProperties(Me)("MyProperty").Attributes

' Checks to see if the value of the BrowsableAttribute is Yes.
If attributes(GetType(BrowsableAttribute)).Equals(BrowsableAttribute.Yes) Then
    ' Insert code here.
End If 

' This is another way to see whether the property is browsable.
Dim myAttribute As BrowsableAttribute = _
    CType(attributes(GetType(BrowsableAttribute)), BrowsableAttribute)
If myAttribute.Browsable Then
    ' Insert code here.
End If

If you marked a class with the BrowsableAttribute, use the following code to check the value.

AttributeCollection^ attributes = TypeDescriptor::GetAttributes( MyProperty );
if ( attributes[ BrowsableAttribute::typeid ]->Equals( BrowsableAttribute::Yes ) )
{
   // Insert code here.
}
AttributeCollection attributes =
    TypeDescriptor.GetAttributes(MyProperty);
if (attributes[typeof(BrowsableAttribute)].Equals(BrowsableAttribute.Yes))
{
    // Insert code here.
}
Dim attributes As AttributeCollection = TypeDescriptor.GetAttributes(MyProperty)
If attributes(GetType(BrowsableAttribute)).Equals(BrowsableAttribute.Yes) Then
    ' Insert code here.
End If

Remarks

A visual designer typically displays in the Properties window those members that either have no browsable attribute or are marked with the BrowsableAttribute constructor's browsable parameter set to true. These members can be modified at design time. Members marked with the BrowsableAttribute constructor's browsable parameter set to false are not appropriate for design-time editing and therefore are not displayed in a visual designer. The default is true.

Note

When you mark a property with Browsable(true), the value of this attribute is set to the constant member Yes. For a property marked with Browsable(false), the value is No. Therefore, when you check the value of this attribute in your code, you must specify the attribute as BrowsableAttribute.Yes or BrowsableAttribute.No.

For more information, see Attributes.

Constructors

BrowsableAttribute(Boolean)

Initializes a new instance of the BrowsableAttribute class.

Fields

Default

Specifies the default value for the BrowsableAttribute, which is Yes. This static field is read-only.

No

Specifies that a property or event cannot be modified at design time. This static field is read-only.

Yes

Specifies that a property or event can be modified at design time. This static field is read-only.

Properties

Browsable

Gets a value indicating whether an object is browsable.

TypeId

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

(Inherited from Attribute)

Methods

Equals(Object)

Indicates whether this instance and a specified object are equal.

GetHashCode()

Returns the hash code for this instance.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute()

Determines if this attribute is the default.

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