asp.net form action

Use
Server.Transfer(URL)
or
Response.Redirect(URL)

And in case you want that the form is not PostedBack i.e. on click of Submit it should go to a new page then switch to the HTML editor in the SDK and in the Form Tag add

Action='URL'

Acturally, I want the <form action> like the regular html <form action> behave, which are name attruble, value attruble, type attruble, input, ect... the action attruble behave will forward the form with controls or contains to other site for processing.
The server.transfer or redirect is redirect to other web page, it doesn't forward with form controls or contains to other web site for processing.
I have a work around, which is build a string with html form attrubles and values using response.write to transter form contrains to other web site for processing.
This may not be the good way, but it works.