Hide the close button of a WPF window
I want to hide the close button of a WPF progress window, to prevent users from closing it manually. It was complicated to achieve, but perfectly doable.
While I could not find a property or function that removes or disables the close button, you can fix it with some obscure DLL hacking :)
First, define two constanst and two methods:
private const int GWL_STYLE = -16;
private const int WS_SYSMENU = 0x80000;
[DllImport("user32.dll", SetLastError = true)]
private static extern int GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
Then, in the window class, call the imported DLL methods as such:
var hwnd = new WindowInteropHelper(this).Handle;
SetWindowLong(hwnd, GWL_STYLE, GetWindowLong(hwnd, GWL_STYLE) & ~WS_SYSMENU);
A convenient way to use this is to wrap the functionality in an extension method:
public static class WindowExtensions
{
private const int GWL_STYLE = -16;
private const int WS_SYSMENU = 0x80000;
[DllImport("user32.dll", SetLastError = true)]
private static extern int GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
public static void HideCloseButton(this Window window)
{
var hwnd = new WindowInteropHelper(window).Handle;
SetWindowLong(hwnd, GWL_STYLE, GetWindowLong(hwnd, GWL_STYLE) & ~WS_SYSMENU);
}
}
If you know a more convenient way to hide the close button (perhaps I just didn’t find the correct property/method), reach out to me and I’ll add it to the post.
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