Application Starting - detecting Shift Key pressed

[Michael Moreno]

Hello,

I would like to cancel an action if the user holds the shift key while
the application is starting-up.
Would you know what is the best way to do so please?


Thanks,
Michael

 

[Marc Gravell]

I'm assuming the main question is about the [Shift] key (not cancelling an
action):

Just test the Control modifiers:

if ((System.Windows.Forms.Control.ModifierKeys & Keys.Shift) == Keys.Shift)
{
System.Diagnostics.Debug.WriteLine("Shift down");
}

This appears to work even for console applications (if you adda a
reference), which is quite nice...

Marc

 

[Michael Bray]

I would like to cancel an action if the user holds the shift key while
the application is starting-up.
Would you know what is the best way to do so please?

If you do it from within the Form class, you can use the 'ModifierKeys'.
If you want to do it from Main(...) or anywhere else outside of the Form,
then you can use PInvoke:

[DllImport("user32.dll")]
static extern short GetKeyState(VirtualKeyStates nVirtKey);

int ks = GetKeyState(VirtualKeyStates.VK_SHIFT);
if ((ks & 0x80) != 0)
{
// SHIFT KEY is pressed
}

BTW the VirtualKeyStates is an enum defined at pinvoke.net:

http://pinvoke.net/default.aspx/user32.GetKeyState

But if you wanted you could just set the PInvoke signature to use an int
and pass 0x10.

-mdb

 

[Marc Gravell]

See my previous post - you don't actually need the PInvoke step, regardless
of whether you are working with a Form subclass.

Marc

 

[Michael Moreno]

Great!!!
Thank you very much

 

[Michael Bray]

See my previous post - you don't actually need the PInvoke step,
regardless of whether you are working with a Form subclass.

Yeah I saw that... that's a good point - thanks for the tip.

-mdb