Page Logic

I wanted to see if this were possible. Ive done it in php not sure how to do it in asp.net
Basically, I want the page to show a login area if the Management.GetUser() returns null.
Would I do this in the aspx page or the cs page...
I was thinking in the aspx page i would have <% if(Management.GetUser != null) {  // show logged in } else { // show login control } %>
For some reason even if im logged in GetUser() is always null but if i checked the Load event of the page in the cs file it returns a valid obj.
Anyone know what I am doing wrong ?

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