Request.QueryString[] is not taking Parameter values.

How can I read a key value from a xml file using request.QueryString[]. Here is the code I have tried, but its showing strActivityID value as null only, if I hardcode the value while debugging only desired page is getting loaded. but I wanted to make it happen at run time automatically.

 

string ArticleID = "Application"

try

{

strActivityID = Request.QueryString[ArticleID];

if (!string.IsNullOrEmpty(strActivityID))

{ strArticleURL = GetUrl(strActivityID);

}

}