You should apply this attribute to a class with a custom designer to indicate the nature of that designer. The design-time environment is entitled to refuse to use your designer if you do not supply this attribute.

The Category should be chosen from one of the standard options (Component, Form, or Generic ) if you wish to integrate with the VS.NET designers. You could extend this with your own custom categories if you are providing your own design-time host.

public sealed class DesignerCategoryAttribute : Attribute {
// Public Constructors
   public DesignerCategoryAttribute();
   public DesignerCategoryAttribute(string category);
// Public Static Fields
   public static readonly DesignerCategoryAttribute Component;  // =System.ComponentModel.DesignerCategoryAttribute
   public static readonly DesignerCategoryAttribute Default;  // =System.ComponentModel.DesignerCategoryAttribute
   public static readonly DesignerCategoryAttribute Form;  // =System.ComponentModel.DesignerCategoryAttribute
   public static readonly DesignerCategoryAttribute Generic;  // =System.ComponentModel.DesignerCategoryAttribute
// Public Instance Properties
   public string Category{get; }
   public override object TypeId{get; }
// overrides Attribute
// Public Instance Methods
   public override bool Equals(object obj);  // overrides Attribute
   public override int GetHashCode();  // overrides Attribute
   public override bool IsDefaultAttribute();  // overrides Attribute
}

Hierarchy

System.Object System.Attribute DesignerCategoryAttribute

Valid On

Class