Вы можете сделать следующее:
[DllImport("user32.dll")]
static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll")]
static extern IntPtr LoadIcon(IntPtr hInstance, IntPtr lpIconName);
[DllImport("user32.dll", EntryPoint = "GetClassLong")]
static extern uint GetClassLong32(IntPtr hWnd, int nIndex);
[DllImport("user32.dll", EntryPoint = "GetClassLongPtr")]
static extern IntPtr GetClassLong64(IntPtr hWnd, int nIndex);
/// <summary>
/// 64 bit version maybe loses significant 64-bit specific information
/// </summary>
static IntPtr GetClassLongPtr(IntPtr hWnd, int nIndex)
{
if (IntPtr.Size == 4)
return new IntPtr((long)GetClassLong32(hWnd, nIndex));
else
return GetClassLong64(hWnd, nIndex);
}
uint WM_GETICON = 0x007f;
IntPtr ICON_SMALL2 = new IntPtr(2);
IntPtr IDI_APPLICATION = new IntPtr(0x7F00);
int GCL_HICON = -14;
public static Image GetSmallWindowIcon(IntPtr hWnd)
{
try
{
IntPtr hIcon = default(IntPtr);
hIcon = SendMessage(hWnd, WM_GETICON, ICON_SMALL2, IntPtr.Zero);
if (hIcon == IntPtr.Zero)
hIcon = GetClassLongPtr(hWnd, GCL_HICON);
if (hIcon == IntPtr.Zero)
hIcon = LoadIcon(IntPtr.Zero, (IntPtr)0x7F00/*IDI_APPLICATION*/);
if (hIcon != IntPtr.Zero)
return new Bitmap(Icon.FromHandle(hIcon).ToBitmap(), 16, 16);
else
return null;
}
catch (Exception)
{
return null;
}
}
Этот код возвращает маленький значок окна, который отображается рядом с текстом окна в заголовке.