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

Yes, it can be done - by creating a custom HtmlForm object and toggling the forms as needed. I've just answered a similar question here (with code):

Paypal Form Ruins My ASP.NET webforms layout -> How to Solve?

Answer 2

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.

Answer 3

As pointed out, this is one of the shortcomings of WebForms. I do want to point out, additionally, that with cross-page posting and validation groups, you can typically reach your desired behavior (for most "multi-form" solutions).

Answer 4

many non server forms - you can , but only one runAt Server form

i also found this :

A server-side form tag is the tag which has a runat="server" attribute. If this attribute is missing, then it's a typical HTML form tag. The conclusion is that you are allowed to use multiple form tags on a page, as long as only one has the runat="server" attribute. The disadvantage of the form that doesn't have this attribute, is that view state won't work (meaning form values will disappear when using the back/forward browser buttons). It's a small price to pay if you really need multiple forms on a page.

Answer 5

Regarding the additional question: the <form runat="server"> is parsed as HtmlForm class behind the scenes, which inherits from HtmlControl like any other HTML element with runat="server".

Unlike any other HtmlControl though, there can exist only one instance per page and it does not appear in the toolbox as it's added automatically to every new Form you create, so it's quite pointless.

Answer 6

1. Take master page & set design.
2. Take one form in master page.
3. Second form take in contain place holder.
4. In contain place holder in only for write form tag (not use)
5. Add aspx page & design second form but not write form tag only for control put
6. Take button click event fire code write

This is proper way of two form