How do I prevent the original form from losing focus when I show another form?

Question

I am having a problem where my main form loses focus when opening a new form. I know I can revert the focus back by using mainForm.focus() , but how do I handle things if I want the main form to never give up its focus when new window is opened?

Answer 1

您可以通过覆盖属性ShowWithoutActivation来实现此ShowWithoutActivation ，以使其在要显示的表单中返回true ，而不会从显示它的表单中获取焦点，在这种情况下，表单将是您的主要表单。

Answer 2

Cody Gray answered this, I'm just expanding it by directly pasting the code. Someone with edit rights can copy it over there and delete this for all I care ;)

pinvoke.net's ShowWindow method.:

    private const int SW_SHOWNOACTIVATE = 4;
    private const int HWND_TOPMOST = -1;
    private const uint SWP_NOACTIVATE = 0x0010;

    [DllImport("user32.dll", EntryPoint = "SetWindowPos")]
    static extern bool SetWindowPos(
         int hWnd,           // window handle
         int hWndInsertAfter,    // placement-order handle
         int X,          // horizontal position
         int Y,          // vertical position
         int cx,         // width
         int cy,         // height
         uint uFlags);       // window positioning flags

    [DllImport("user32.dll")]
    static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);

    static void ShowInactiveTopmost(Form frm)
    {
        ShowWindow(frm.Handle, SW_SHOWNOACTIVATE);
        SetWindowPos(frm.Handle.ToInt32(), HWND_TOPMOST,frm.Left, frm.Top, frm.Width, frm.Height,SWP_NOACTIVATE);
        frm.TopMost = false;
    }