I'm building a website in asp.net and c# and I want to have ONE PAGE and to change content of a div -> section. So I used innerHTML for this and it works fine fot HTML pages (one page for each section), but I want to reuse aspx file (asp.net controls, code, etc.), not just HTML. Now innerHTML does not work. I like having one central page, not that kind of website with almost an identical page for each section. If you want to change something (design in most cases) you should change all of them no?
Does anyone know the best way to change content and having a central page? I done this in PHP (with "require()") but I don't know how to do this with asp.net. I tried. THANK YOU !

thanks, i use a masterpage now. I have "Default.aspx","Master.master","Home.aspx","News.aspx" pages and I set up the LinkButtons from my menu, in Default.aspx to redirect the content pages like this:

Response.Redirect("Home.aspx");// for a menu link

 Response.Redirect("News.aspx");//for another menu link

It's just one problem. After I click one menu link, the content appears, but after that when I click the other menu link the content it's not appearing. It's the same content that appeared after first click. It's first time I use a Master Page so please help me if you can, to get the right content for every link button. THANKS !

You need the links on your master page. Better to use HTML links like <a href="News.aspx"></a> as button links can be problematic on mobile devices.