Is it possible to reload same page position and size in asp .net web form

A page does not have position and size; this is the attribute of the Web browser window.

Such things are possible, but I would not recommend it. And they are not related to ASP.NET. This is all about Javascript. Please see:
http://www.w3schools.com/jsref/met_win_open.asp[^],
http://www.w3schools.com/jsref/obj_window.asp[^],
http://www.w3schools.com/jsref/met_win_resizeby.asp[^],
http://www.w3schools.com/jsref/met_win_resizeto.asp[^],
http://www.w3schools.com/jsref/met_win_moveby.asp[^],
http://www.w3schools.com/jsref/met_win_moveto.asp[^].

Note that you can return a window object if you create a new one any modify your size/location later.

Why this stuff is not good to deal with? First of all, with the advent of tabs (which are very good), in general case, you don't know what is the window of your page. It could be a tab page. Even if you window.open (which is itself not recommended some cases, because the users usually don't like popups), you can actually create either a separate window, or a tab. It depends on the parameters of the call; and the result probably depends on the browser (anyway, I never heard that this aspect was ever standardized or even documented).

This is really a good idea to leave the location of the window or a tab to the user.

—SA