How to filter a key press the right way (C#)

[Cyron43]

Hi guys,
there are times when I face a certain problem when I create mods. I set a specific key for an action (let's say Ctrl+T) and then when I test my mod I get a response from another mod written by someone else. His description claims one has to press T. Yes, just T and not Ctrl+T. There is just one keyboard but a gazillion mods and so I think it's about time to teach you how to do it right, for the sake of the modder community. Here is a typical KeyDown event handler:

private void OnKeyDown(object sender, KeyEventArgs e){   if(e.KeyCode == Keys.T)   {      // do something...   }}

Do your KeyDown handlers look like this (or KeyUp handler, that doesn't matter)? Then you're doing it wrong! This method doesn't care if you press either Ctrl, Shift and/or Alt in addition.
Here is how to do it right:

private void OnKeyDown(object sender, KeyEventArgs e){   if(!e.Alt      && !e.Control      && e.KeyCode == Keys.T      && !e.Shift)   {      // do something...   }}

This assures your mod reacts only on T but not to any other combination with T. So the combinations are still free for other mods.
Another example. Let's say you want to handle Ctrl+Shift+X (watch closely for the exclamation marks).

private void OnKeyDown(object sender, KeyEventArgs e){   if(!e.Alt      && e.Control      && e.KeyCode == Keys.X      && e.Shift)   {      // do something...   }}

Edited December 13, 2015 by Cyron43

[MrGTAmodsgerman]

Danke, eine Frage, ist die Reihenfolge egal? Also z.B

private void OnKeyDown(object sender, KeyEventArgs e){   if(!e.Alt      && e.Control      && e.Shift)      && e.KeyCode == Keys.X   {      // do something...   }}

?

[Cyron43]

Danke, eine Frage, ist die Reihenfolge egal? Also z.B

private void OnKeyDown(object sender, KeyEventArgs e){   if(!e.Alt      && e.Control      && e.Shift)      && e.KeyCode == Keys.X   {      // do something...   }}

?

Ja, das ist hier egal.

Edited October 15, 2015 by Cyron43