Custom and User control

Hi Rajesh

Custom controls:

 A control authored by a user or a third-party software vendor that does not belong to   the .NET Framework class library. This is a generic term that includes user controls.A  custom server control is used in Web Forms (ASP.NET pages). A custom client control is used  in Windows Forms applications.

UserControls:
In ASP.NET: A user-authored server control that enables an ASP.NET page to be re-used  as a server control. An ASP.NET user control is authored declaratively  and persisted as a  text file with an .ascx extension. The ASP.NET page framework compiles a user control on  the fly to a class that derives from the System.Web.UI.UserControl class.


User control

1) Reusability web page
2) We can't add to toolbox
3) Just drag and drop from solution explorer to page (aspx)
4) U can register user control to. Aspx page by Register tag
5) A separate copy of the control is required in each application
6) Good for static layout
7) Easier to create
8)Not complied into DLL
9) Here page (user page) can be converted as control then
We can use as control in aspx

Custom controls

1) Reusability of control (or extend functionalities of existing control)
2) We can add toolbox
3) Just drag and drop from toolbox
4) U can register user control to. Aspx page by Register tag
5) A single copy of the control is required in each application
6) Good for dynamics layout
7) Hard to create
8) Compiled in to dll


Refer also

http://www.codeproject.com/KB/user-controls/UserControlDesigner.aspx


Thanks