Can an ASPX file contain more than one form marked with runat="server" in ASP.NET?
No, an ASPX file in ASP.NET cannot contain more than one 'form' element with the runat="server" attribute. The reason is that ASP.NET is built on the Web Forms model, which follows a single-form submission architecture.
The 'form' element with the runat="server" attribute is the server-side form that encapsulates the ASP.NET controls and enables server-side event handling and postback functionality. It acts as the container for controls like buttons, textboxes, and other input elements.
Having multiple 'form' elements with runat="server" in an ASPX file would lead to conflicts and inconsistent behavior. It would result in multiple form submission targets and break the fundamental model of ASP.NET Web Forms.
If you have multiple sections in your ASPX page that require server-side processing and interaction, you can use panels or other container controls like 'div' or 'table' to group related controls. However, only one 'form' element should be present with runat="server" to maintain the proper functionality of ASP.NET Web Forms.