[ASP. NET secret Reading Notes] user-defined controls

User-Defined controls can include:
1. Static content
2. Dynamic Content (for dynamic content, the attributes of those controls cannot be used directly. You can use attributes to expose the attributes of these controls, or use a hashtable to set the relevant attributes of all controls to directly expose this hashtable .)
3. Custom Controls have their own event processing capabilities
4. You can use loadcontrol (PATH) to program and control the loading of custom controls. You can also perform some downward transformation to specific controls for some control. Some websites use multiple user-defined controls to define some skins. When a user chooses to load the custom controls, the skin is changed.