I have a winforms application where in I have a textbox inside a form. I need to set focus to the textbox whenever I press 'Ctrl+F'. I have the following code in keyup event.
private void frm_KeyUp(object sender, KeyEventArgs e)
{
// Handle 'Ctrl + F' to Find
if (e.KeyData == (Keys.Control | Keys.F))
SetFocus();
}
Problem I have here is that sometimes, even though the focus is on form and I try 'Ctrl+F' the condition doesn't run. I know, as soon as I press 'Ctrl' the event gets fired even before I would have pressed key 'F'. Eventually it works, when I press both the keys at the very same time. So to the user it might look like the screen is unresponsive to the keys sometimes.
How can I overcome this situation?
You're using the KeyUp event and checking if the event contains both keys. This will only happen when you release both keys at the same time.
Change it to the KeyDown event instead, and check whether Ctrl was pressed at the moment F was pressed:
if (e.Control && e.KeyCode == Keys.F)
{
// ...
}
Related
I am developing a small application with some buttons and textbox. What I am having problem is assigning a keyboard key (e.g. F3) to a button click.
For example if the user click the button Cash the code I wanted it's executed fine, but I want to make more easier instead clicking the button with mouse, I want the user be able to press the key on keyboard. I used the keydown event, also keypress event of that button, but still nothing.
I tried this keydown event
if (e.KeyCode == Keys.Enter)
{
btncash.PerformClick()
}
But still nothing
Do not use F3 function button it's used by OS for activating search. Enter key is fairs click event on focused control so do not use this also. Implement as suggested below.
In your Main form
Set KeyPreview to True in form load event.
Add KeyDown event handler with the following code
private void Form1_KeyDown(object sender,
KeyEventArgs e)
{
if (e.Control && e.KeyCode == Keys.H)
{
btncash.PerformClick();
//btncash_Click(null, null);
}
}
I have a NumericUpDown control in WinForms. The Up/Down arrow keys increase/decrease the value by 1. I want to map the PageUp/PageDown keys for larger increments.
The Control.KeyPress event does not get fired with the PageUp/PageDown keys and if I use the Control.KeyUp/Control.KeyDown events, the combination fires only once even if the user keeps the keys pressed for a while.
How could I trap multiple PageUp/PageDown keys presses during long key presses?
Strange to say, but I cannot reproduce this issue. I have a new winform instance, numericUpDown control with default property` values and KeyDown event handler works perfectly with long key press:
private void numericUpDown1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.PageDown)
numericUpDown1.Value -= 10;
else if (e.KeyCode == Keys.PageUp)
numericUpDown1.Value += 10;
}
Can you provide your code in the event handlers?
/Sorry, I know Im not supposed to ask for clarification in the answer, but I can`t write comments./
I'm using WPF KeyDown event. Can you please explain why this condition is true, when I press Ctrl+F1? When I press F1, Ctrl is already pressed so !Keyboard.IsKeyDown(Key.LeftCtrl) should be false.
Edit:
In the code below if you press Ctrl+F1 both messages would fire. But if you change the order of these two if statements, only "ctrlF1" message would fire like it should be. I would like to get explanation of that strange behavior.
private void Window_KeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.F1 && Keyboard.IsKeyDown(Key.LeftCtrl))
{
MessageBox.Show("ctrlF1");
}
if (e.Key == Key.F1 && !Keyboard.IsKeyDown(Key.LeftCtrl))
{
MessageBox.Show("F1");
}
}
The difference is as follows:
In the code you showed, when entering the handler, F1 is pressed and Ctrl is pressed (both conditions of first if-clause are true). MessageBox blocks the thread. Meanwhile you release the Ctrl key and click at the message. Then code execution goes on and Ctrl key is no longer pressed (both conditions of the second if-clause are true)
If you switch the if-statements, only the first condition (e.Key == Key.F1) of the first if-statement is true. Execution comes to second if-statement and both conditions are true. MessageBox is shown and execution stops till the MessageBox is closed.
The difference is: Pressing of the F1 key is evaluated before the handler is called, but the check Keyboard.IsKeyDown(Key.LeftCtrl) is evaluated in the moment, when the line of code is executed
Basically in a C# Windows Form Application I am working on I have 2 buttons I press button1 and button2.
How do I make it when I press 2 custom keys simultaneously(eg. CTRL+L) the program does the steps coded for button1? Keeping in mind that the window might not be active.
I have looked at this: Keypress To Simulate A Button Click in C# but I don't think this would work if the window isn't active, and its also only one button pressed not two.
In Form KeyUp Event and the Properties is KeyPressPreview = true you can achieve this task.
private void Form_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.L && e.Control)
{
yourButton.PerformClick();
e.Handled = true;
}
}
or
if you want in Keypress Event
private void Form_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.Control && e.KeyCode == Keys.L)
{
yourButton.PerformClick();
e.Handled = true;
}
}
EDIT:
I realized that the OP want to the keypress Event from his statement "but I don't think this would work if the window isn't active"
You probably must check this
How to set a Windows hook in Visual C# .NET
If you precede any character in the button text with &, and keep UseMnemonic to true,. the alt+character will serve as shortcut key.
For example, in your case change the text of the buttons to button&1 and button&2 respectively. Keep UserMnemonic = true. Now if you press alt+1 then button1 will be pressed and if you press alt+2, button2 will be pressed.
Also 1 and 2 respectively will be underlined.
Hope that helps.
Is there a way to start a method in C# if a key is pressed? For example, Esc?
use the OnKeyPress Event of your textbox and in the event
if(e.KeyCode==Keys.Escape)
{
yourTextBox.Text = string.Empty;
}
As others have mentioned, handle the KeyDown or KeyUp event of the appropriate control. The KeyPress event would work for the Escape key as well, though it will not trigger for some keys, such as Shift, Ctrl or ALt.
If you want to execute this function anytime the user presses the Escape key, then you probably want to handle the event on the Form. If you do this, you will probably also want to set the Form's KeyPreview property to true. This will allow the Form control to receive the event even if the focus is currently inside of one of the child controls.
If you want the behavior to be specific to a control, such as clearing the text within a textbox that currently has focus, then you should handle the KeyDown or KeyUp event of the TextBox control. This way, your event handler will not be triggered if the user presses the escape key outside of the textbox.
In some situations you might want to prevent child controls from handling the same event that you've just handled. You can use the SuppressKeyPress property on the KeyEventArgs class to control this behavior:
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Escape)
{
MessageBox.Show("Escape key pressed");
// prevent child controls from handling this event as well
e.SuppressKeyPress = true;
}
}
In case someone is looking for how to do this in a console application
if (Console.ReadKey().Key == ConsoleKey.Escape)
{
return;
}
I am writing WinForms application. User fills the textbox and if he wants to delete everything, he just clicks esc key on keyboard
I think you need to handle the KeyDown event.
You have to switch the form property "KeyPreview" to true or your events will not be fired. Handling these events alone will not do anything even though the events are correct. It will look to you like nothing really happens even though you have subscribed the proper event handlers.
First in Properties do > KeyPreview : True
Then :
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Escape)
{
//call your method here
}
}
Are you writing a Console application, a WinForms application or something else? Are you trying to capture the ESC key at all times (regardless of the focused window/application) or something else?
More context required.
If you're writing a Console app, then you should start looking at things like Console.ReadKey...
http://msdn.microsoft.com/en-us/library/system.console.readkey.aspx
With Event KeyPress...
//Escape
if (e.KeyChar == '')
{
this.DialogResult = DialogResult.Cancel;
e.Handled = true;
}
You can use KeyUp event too. I prefer it though.
private void Window_KeyUp(object sender, System.Windows.Input.KeyEventArgs e) {
if (e.Key == Key.Escape) {
//WHAT WILL HAPPEN INSERT HERE
}
}
The basic answer is listed here several time
Implement Form_KeyDown
Private Sub frmCustomerSearch_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown
Try
If e.KeyCode = Keys.Escape Then
ClearFindForm()
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
Set form.keyPreview
form.KeyPreview = true
The additional thing you need to check is whether you have a button capturing ESC so it can be the form.cancelButton
to be sure ...
form.CancelButton = nothing
This is sneaky. If you have set that and forgot about it, the Escape key will not trigger the KeyDown event.
I was led to this because a button set to be the form.CancelButton does not seem to fire if it is invisible or on a non visible tab,so KEYDOWN is your only option.