确定点击了哪个TabPage

虽然此方法未使用二分查找，但它可以处理多行选项卡页。

private static int
GetTabIndexAt
(
    System.Windows.Forms.TabControl tabControl
,
    System.Drawing.Point point
)
{
    int result = -1;

    if (tabControl != null)
    {
        for (int i = 0; i < tabControl.TabPages.Count; i++)
        {
            System.Drawing.Rectangle rect = tabControl.GetTabRect(i);
            if (rect.Contains(point))
            {
                result = i;
                break;
            }

        }
    }
    return (result);
}