解决Silverlight中DataGrid在显示数据时多一空白列

/* 但是，这个只是把空白列的宽度设小点 */
void dg_sql_data_SizeChanged(object sender,SizeChangedEventArgs E) 
    { 
        DataGrid myDataGrid = (DataGrid)sender; 
         
        if (myDataGrid.RenderSize.Width != 0) 
        { 
            double all_columns_sizes = 0.0; 
            foreach (DataGridcolumn dg_c in myDataGrid.columns) 
            { 
                all_columns_sizes += dg_c.ActualWidth; 
            } 
            //可通过调整 18这个数字来控制空白列的宽度
            double space_available = (myDataGrid.RenderSize.Width - 18) - all_columns_sizes; 
            foreach (DataGridcolumn dg_c in myDataGrid.columns) 
            { 
                dg_c.Width = new DataGridLength(dg_c.ActualWidth + (space_available / myDataGrid.columns.Count)); 
            } 
        } 
    }