Find Actice TAB in IE7

if (sbc.ToString().IndexOf("TabWindowClass", 0) > -1)
{
StringBuilder childsb = new StringBuilder(100);
IntPtr hChildWnd = GetWindow(hwnd, GW_CHILD);
while (IntPtr.Zero != hChildWnd)
{
GetClassName(hChildWnd.ToInt32(), childsb, 100);

if (childsb.ToString().Contains("Shell DocObject View"))
{
IntPtr visWin = FindWindowEx(hChildWnd, IntPtr.Zero, "Internet Explorer_Server", IntPtr.Zero);
if (IsWindowVisible(visWin))
{
hwnd = visWin;
break ;
}

}
hChildWnd = GetWindow(hChildWnd, GW_HWNDNEXT);
}