asp.net - Can we use multiple forms in a web page?

Question

So far, all the web pages I met contain at most one <form> tag. Why not multiple ones? I can not think of reasons why multiple forms can't coexist within the same web page.

Also, to be specific to ASP.NET - why are all the server controls are placed within the <form> tag? Why not place them somewhere else?

Plus,

I noticed that in an .aspx file, the <form> tag has the runat=server attribute, while a normal server control such as Button also has one. So it seems the <form> is also a server control. But strangely enough, I cannot find it in the Visual Studio Toolbox.

Answer 1

There can be multiple forms, with hacks.

It is indeed a shortcoming of WebForms. In ASP.NET MVC you can implement as many forms as you want (and it is valid & correct behavior of web pages).

The reason all server controls are placed inside <form> tag is to allow the WebForms engine to recognize them, load their values & save their values from/to the ViewState. Almost all infrastructure of control management in WebForms is based on the idea that a tag contains everything you access from the code-behind.