How to bind the values to gridview?

Thanks...i am generating DataTables, DataColumns, DataRows on runtime and bind it to GridView ....
this is my code for that....
 
NodeEnumerator myEnumerator = new NodeEnumerator(this.UltraWebTree1);
        string s = string.Empty;
        string s1 = string.Empty;
        while (myEnumerator.MoveNext())
        {
         
                //s += myEnumerator.Current.Text + ": Level: "
                //  + myEnumerator.Current.Level.ToString() + "
" +  myEnumerator.Current.TargetUrl +  "
" ;
                s = myEnumerator.Current.Text;
                s1 = myEnumerator.Current.TargetFrame;

            }
            //Response.Write(s);
            DataTable dt = new DataTable();
            dt.Columns.Add("Name");
            dt.Columns.Add("TargetUrl");
            DataRow dr = dt.NewRow();
            dr["Name"] = s;
            dr["TargetUrl"] = s1;
            dt.Rows.Add(dr);
            DataSet ds = new DataSet();  
            ds.Tables.Add(dt);
            GridView1.DataSource = ds;
            GridView1.DataBind();
       
    }
 
 
 
but it shows the last value of ultrawebtree....it is not bind all the values...how can i do this...give me the solution...