Writing xml output to asp .net webpage

 Hi all,
 
I am a complete newbie to asp .net. Here is my problem.

 A user can enter a URL like "http://........../default.aspx?xx=11&yy=22&zz=33"
I need to use the parameters xx,yy and zz and run a stored procedure and get data. Then I have to display this data as xml content. I can form a xml file but I am not able to display it as xml as it is in the file. If I load the xml file stored on the disk using document source then it just displays the contents as a string without the tags and no formatting either. Even is there a way to avoid writing to a file and then displaying?
 
Thanks in advance. 
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