src in img tag to add on a url string path asp.net

Hey guys,

I'm trying to show a picture in a table tr however I am populating the table dynamically ie using a repeater. The field(PictureURL) the just the pic name eg.john_doe.jpg . In asp i was able to do show the pic by having a a string url that have the path to which the pic is stored and then call for the name of the pic. like src="=url&rsUser("PictureURL")"

However I am using asp.net and have no idea how to get the url which is now stored in a session variable to add on to the scr. All i have is the following
[PHP]<asp:Repeater ID="rep" DataSourceID="SqlDataSource3" runat="server">
                        <ItemTemplate>
                        <tr&g ...