I wondered if anyone could provide assistance on the best way in which to 
provide the following in a custom server control.

What I want to do create is a server control, which displays one user 
interface when initially displayed. It will contain two different type of 
submit buttons, one of them just posts back and basically just raises an 
event but doesn;t change the user interface in anyway. However the other 
button posts back, but on post back I would like to be able to display a 
different user interface entirely. This will allow more advanced selection 
on the control, and then be able to post back from this user interface you 
the original user interface.

I want the control to always be on the same form and the display to be 
either one interface or the other. i don't want both displayed at once and 
I don't a combination of both. 

I could write this as an aspx form no problems, but the propblem I have is 
that I want to encapsulate all of this into one custom server control.

I have started by creating a composite server control and using 
createchildcontrols to provide the original user interface. The second 
button is implemented by adding a asp button control and assigning an 
event to the click event of the control. The problem is that when the post 
back occurs the createchildcontrols is fired before the event handler for 
the buton is fired. Therefore the controls are already added to the page 
before the submit event is called which is where I wanted to create the 
second user interface.

How would I get round this, or should I even be considering doing this. 
Two approaches I think might work would be to 1. in createchildcontrols 
check to see if page.postback  is true and display the second user 
interface. This would be a problem when going back to the first user 
interface because this would also be a postback. or 2. split both of the 
user interfaces into seperate controls in their own right. And then use a 
web form to glue the pieces together as required.

Would anyone be able to provide their thoughts on whether I am on the 
right lines or whether there would be a better way to acheive this.

Thanks