How to get IsKeyDown method to work in C#

Question

I can’t figure out how get this method to work:

System.Windows.Input.Keyboard.IsKeyDown(System.Windows.Input.Key)

The object browser says the following:

public static bool IsKeyDown(System.Windows.Input.Key key)
Member of System.Windows.Input.Keyboard
Summary:
Determines whether the specified key is pressed.
Parameters:
key: The specified key.
Return Values:
true if key is in the down state; otherwise, false.

Okay, so it’s a member of Keyboard, right? I used the following code: Keyboard test = new Keyboard();

But when I type test and then the dot, IsKeyDown is not an option. The only options are from the Windows.Forms members. What am I missing here? Thanks.

Solution 1

Add PresentationCore.dll assembly as a reference.

Add WindowsBase.dll assembly as a reference.

Test code:

private void buttonMisc_Click(object sender, EventArgs e)
{
    if (System.Windows.Input.Keyboard.IsKeyDown(System.Windows.Input.Key.LeftShift) == true)
        MessageBox.Show("Got it!");
}

Solution 2

IsKeyDown is static, so you need to use it like

Keyboard.IsKeyDown()

Not with an instantiated object.

You also need to make sure you have the correct using statement at the top:

using System.Windows.Input;

EDIT

On further inspection, Keyboard is a static class... So you can't Keyboard test = new Keyboard();

Comments

[FrostyFire]

I'm not sure what you mean. As I type your code, after pressing the dot, the method does not come up. Do I need to add a special reference aside from PresentationCore?

[Justin Self]

@user1739957 You should be able to simply type Keyboard.IsKeyDown(Key.A)

[FrostyFire]

Nope! Its not an option after I type the dote!

[Yinda Yin]

So you're detecting a key down when the user is clicking a button with the mouse? :/

[Steve Wellens]

Yep. I get the message box when I hold the left shift down and click the button with the mouse.

[Justin Self]

@user1739957 If you have Keyboard test = new Keyboard, you need to remove that because it won't compile.

[FrostyFire]

Thanks so much, Steve Wellens. It worked great. I altered it a little and it works even when the form is minimized. As a matter of fact when I pressed shift for the first letter, the message came up. Thanks again!

[JonP]

This helped me to detect if Left Shift is held down when a menu item is clicked. The Microsoft help for IsKeyDown is incomplete, it mentions that you need assembly PresentationCore (which provides the Keyboard class) but fails to mention WindowsBase (which provides the Key class with all the key definitions).