Get ColumnIndex By DataColumn and HeaderText in Gridview

static public int GetColumnIndexByDBName(GridView aGridView, String ColumnText)
    {
        System.Web.UI.WebControls.BoundField DataColumn;
        for (int Index = 0; Index < aGridView.Columns.Count; Index++)
        {
            DataColumn = aGridView.Columns[Index] as System.Web.UI.WebControls.BoundField;
            if (DataColumn != null)
            {
                if (DataColumn.DataField == ColumnText)
                    return Index;
            }
        }
        return -1;
    }
static public int GetColumnIndexByHeaderText(GridView aGridView, String ColumnText)
    {
        TableCell Cell;
        for (int Index = 0; Index < aGridView.HeaderRow.Cells.Count; Index++)
        {
            Cell = aGridView.HeaderRow.Cells[Index];
            if (Cell.Text.ToString() == ColumnText)
                return Index;
        }
        return -1;
    }