public static void SetSortIcon( this ListView lv, int columnIndex, SortOrder order )
{
IntPtr columnHeader = SendMessage ( lv.Handle, LVM_GETHEADER, IntPtr.Zero, IntPtr.Zero );
for ( int columnNumber = 0; columnNumber <= lv.Columns.Count - 1; columnNumber++ ) {
IntPtr columnPtr = new IntPtr ( columnNumber );
LVCOLUMN lvColumn = new LVCOLUMN ( );
lvColumn.mask = HDI_FORMAT;
SendMessage ( columnHeader, HDM_GETITEM, columnPtr, ref lvColumn );
if ( !( order == System.Windows.Forms.SortOrder.None ) && columnNumber == columnIndex ) {
switch ( order ) {
case System.Windows.Forms.SortOrder.Ascending:
lvColumn.fmt &= ~HDF_SORTDOWN;
lvColumn.fmt |= HDF_SORTUP;
break;
case System.Windows.Forms.SortOrder.Descending:
lvColumn.fmt &= ~HDF_SORTUP;
lvColumn.fmt |= HDF_SORTDOWN;
break;
}
} else {
lvColumn.fmt &= ~HDF_SORTDOWN & ~HDF_SORTUP;
}
SendMessage ( columnHeader, HDM_SETITEM, columnPtr, ref lvColumn );
}
}
internal static extern IntPtr SendMessage( IntPtr hwnd, Int32 msg, IntPtr wParam, ref LVCOLUMN lParam );
private static extern IntPtr SendMessageLVCOLUMN(IntPtr hWnd, Int32 Msg, IntPtr wParam, ref LVCOLUMN lPLVCOLUMN);