Show Repeated Data Into Gridview??

This Is my code which is display three row but three row record same.
 
 void FillGridViewPURDET(object sender,EventArgs e)
    {
        string connection = dbconnection.Connection();
        SqlConnection con = new SqlConnection(connection);
        con.Open();
 SqlCommand cmd=new SqlCommand("SELECT *FROM PURDET WHERE PUR_RID='" + TBoxRID.Text + "'",con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
        DataTable ds = new DataTable();
        da.Fill(ds);
 foreach (DataRow row in ds.Rows)
        {
            foreach (GridViewRow row1 in GRDPURDET.Rows)
            {
               & ...