Why can't I refresh the Asp.net page online? Is there a good solution ??

Why is there a submit button in A. aspx of one of my pages, in page_load:
Private void page_load (Object sender, system. eventargs E)
{
// Place user code here to initialize the page
Strreportcode = context. Request. querystring ["reportcode"];
Httpcookie cookie = request. Cookies ["myfirstcookie"];
If (! Ispostback)
{
Binddropdownlist (); // bind the dropdownlist

Bindhour (); // bind dropdownlist
Bindsolvewayname (); // bind the dropdownlist
Bindserveway (); // bind dropdownlist
Lbname. Text = cookie ["servername"]. tostring (); // value lable
}

}
Private void btnadd_click (Object sender, system. eventargs E)
{
// Insert records into the database
}

Btnadd_click () is automatically executed every time you refresh the page, and the button is also displayed when you click the back button of the browser. I think the page_load function must be executed first each time the page is refreshed. However, my page_load () does not call btnadd_click.
What's wrong?

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