title: get url of items in sharepoint document library
body: <p>i have a document library in sharepoint</p>
  
  <p>what is the field called for the url of the uploaded documents?
  see commented line below to see what i am trying to do</p>
  
  <pre><code>SPDataSource dataSource = new SPDataSource();
  dataSource.List = site.RootWeb.Lists["myList"];
  
   this.myDropDownList.DataSource = dataSource;
   this.myDropDownList.DataTextField = "Name";
   //this.myDropDownList.DataValueField = "URL";// what should this be??
   this.myDropDownList.DataBind();
  </code></pre>