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 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)
{
// ...
}
I use these codes to inform users when they press a button and show them in a message box that you have pressed a button. In the winform I have a button, so these codes won't working until I change button1 tabstop to false. and when I click on the button after that it won't tell users that they're pressing a button.
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.A)
{
MessageBox.Show("You have pressed A");
}
}
These codes won't working until I change tabstop of the button to false. Help to how can I do that and let the users know when they pressed a button in any time.
Any help will be appreciated
Set the KeyPreview property of form to true from designer. It will work
I am writing a C# barcode application. I have a EAN-13 regex to detect barcodes in "Form1_KeyPress" function. I have no mechanism to detect where the input comes from. Here is my problem:
I have a reset button in the form which clears all fields and barcodes listed in a dataGridView. When I clicked on it, it gets focus as normal. When it has focus, if I read a barcode via barcode scanner, the newline at the end of each barcode reading causes this button to be clicked thus clearing all fields. So barcodes read are added to dataGridView but immediately deleted due to activation of reset button.
My current solution is to focus on a read-only textbox at the end of each "button_Click" function, but I don't want to write an irrelevant line at the end of each "click" function of buttons. What do you recommend? (by the way I cannot prevent surpress enter key in form's keydown function)
You can't capture the Enter key in the form's keystroke events because it is handled by the button.
If you add:
private void button_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
e.IsInputKey = true;
}
}
to a button then the Enter key won't cause the button to be clicked, and you will see a Form_KeyDown event for it.
You don't want to add this to every button, so create a simple UserControl which is just a button with this code added.
Update
This doesn't work for the space bar. If you set form.KeyPreview = true and add:
private void form_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Space)
{
e.Handled = true;
}
}
then the space bar won't press the button but it will still work in text boxes.
I don't know why Space and Enter behave differently.
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.