Class [attribute extension] and attribute [attribute extension] (to be improved)

Class 1 [attribute extension]
(1) toolboxdata
Specifies whether a property or event should be displayed in the "properties" window. The default value is "true ".
(2) defaultevent
Specifies the default tag generated when you drag a custom control from a toolbox such as Visual Studio.

2. Attribute [attribute extension]
(1) browsable
Specifies whether a property or event should be displayed in the "properties" window. The default value is "true ".
(2) Description
Description of property or event.
(3) defaultvalue
Specifies the default value of the property.
(4) Category
Specifies the name of the attribute or event group category when the property or event is displayed in a propertygrid control set to "sort order" mode.