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CategoryAttribute Class

Specifies the name of the category in which to group the property or event when displayed in a PropertyGrid control set to Categorized mode.


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

public class CategoryAttribute : Attribute

The CategoryAttribute type exposes the following members.

Public methodCategoryAttribute()Initializes a new instance of the CategoryAttribute class using the category name Default.
Public methodCategoryAttribute(String)Initializes a new instance of the CategoryAttribute class using the specified category name.

Public propertyStatic memberActionGets a CategoryAttribute representing the Action category.
Public propertyStatic memberAppearanceGets a CategoryAttribute representing the Appearance category.
Public propertyStatic memberAsynchronousGets a CategoryAttribute representing the Asynchronous category.
Public propertyStatic memberBehaviorGets a CategoryAttribute representing the Behavior category.
Public propertyCategoryGets the name of the category for the property or event that this attribute is applied to.
Public propertyStatic memberDataGets a CategoryAttribute representing the Data category.
Public propertyStatic memberDefaultGets a CategoryAttribute representing the Default category.
Public propertyStatic memberDesignGets a CategoryAttribute representing the Design category.
Public propertyStatic memberDragDropGets a CategoryAttribute representing the DragDrop category.
Public propertyStatic memberFocusGets a CategoryAttribute representing the Focus category.
Public propertyStatic memberFormatGets a CategoryAttribute representing the Format category.
Public propertyStatic memberKeyGets a CategoryAttribute representing the Key category.
Public propertyStatic memberLayoutGets a CategoryAttribute representing the Layout category.
Public propertyStatic memberMouseGets a CategoryAttribute representing the Mouse category.
Public propertyTypeIdWhen implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
Public propertyStatic memberWindowStyleGets a CategoryAttribute representing the WindowStyle category.

Public methodEqualsReturns whether the value of the given object is equal to the current CategoryAttribute.. (Overrides Attribute.Equals(Object).)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeReturns the hash code for this attribute. (Overrides Attribute.GetHashCode().)
Protected methodGetLocalizedStringLooks up the localized name of the specified category.
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodIsDefaultAttributeDetermines if this attribute is the default. (Overrides Attribute.IsDefaultAttribute().)
Public methodMatchWhen overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

Explicit interface implemetationPrivate method_Attribute.GetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute.GetTypeInfoRetrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute.GetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute.InvokeProvides access to properties and methods exposed by an object. (Inherited from Attribute.)

A CategoryAttribute indicates the category to associate the associated property or event with, when listing properties or events in a PropertyGrid control set to Categorized mode. If a CategoryAttribute has not been applied to a property or event, the PropertyGrid associates it with the Misc category. A new category can be created for any name by specifying the name of the category in the constructor for the CategoryAttribute.

The Category property indicates the name of the category that the attribute represents. The Category property also provides transparent localization of category names.

Notes to Inheritors

If you use category names other than the predefined names, and you want to localize your category names, you must override the GetLocalizedString method.

The CategoryAttribute class defines the following common categories:




Properties related to available actions.


Properties related to how an entity appears.


Properties related to how an entity acts.


Properties related to data and data source management.


Properties that are grouped in a default category.


Properties that are available only at design time.


Properties related to drag-and-drop operations.


Properties related to focus.


Properties related to formatting.


Properties related to the keyboard.


Properties related to layout.


Properties related to the mouse.


Properties related to the window style of top-level forms.

For more information, see Extending Metadata Using Attributes.

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

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

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

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

// Gets the attributes for the property.
 AttributeCollection attributes = 

 // Prints the description by retrieving the CategoryAttribute.
 // from the AttributeCollection.
 CategoryAttribute myAttribute = 

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.