asp.net - Error: Request is not available in this context -

i have code in global.asax

void application_start(object sender, eventargs e)       {          // code runs on application startup           if (request.cookies["mylang"] == null)           {               httpcookie mylang = new httpcookie("mylang");               mylang.value = "fa";             mylang.expires = datetime.now.addyears(1);             response.cookies.add(mylang);             session.add("mylang", "fa");         }         thread.currentthread.currentuiculture = new cultureinfo(request.cookies["mylang"].value);         thread.currentthread.currentculture = cultureinfo.createspecificculture(request.cookies["mylang"].value);         session["mylang"] = request.cookies["mylang"].value;     } 

but when run website below error shown:

request not available in context

why?

application_start called once before asp files processed. why request not available yet.

you want use application_beginrequest called on each request.

void application_beginrequest(object sender, eventargs e) {    config.init();     // code runs on application startup    if (request.cookies["mylang"] == null)    {       ...    } } 

application_start vs application_beginrequest event in global.aspx