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C# Loop in KeyPressEventArgs

I have the following event registered:
tb1.KeyPress += new KeyPressEventHandler(tb1KeyDown);
It does this:
public void tb1KeyDown(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Enter)
{
// Do my stuff
e.Handled = true;
}
}
But, if I have entered the Enter key 2 times or more, my tb1KeyDown is in a loop for so often, that I have entered the Enter key.
What am I doing wrong here?
Greetz padde

Detecting Enter key press on a button c#

This piece of code detect most keys and puts it in a messageBox, but one of the keys it doesn't is the enter key. *Note it is a key_down method
MessageBox.Show(e.KeyData.ToString());
so far I have tried so many methods to fix and searched a lot for an answer
I have tried this
private void button1_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
MessageBox.Show("this is it");
e.IsInputKey = true;
}
}
it says 0 references which I know I'm not calling the method but where do I call it?
where ever I do call it, it gives an error.

you delete this line
e.IsInputKey = true;
private void button1_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
MessageBox.Show("this is it");
//e.IsInputKey = true;
}
}
or
private void button1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
MessageBox.Show("this is it");
//e.IsInputKey = true;
}
}

In your Form1 Design Properties:
AcceptButton Property set dropdown to button1 or the name of your Button
KeyUp Event of your Button
private void button1_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
MessageBox.Show("Enter key has been pressed");
}
}
or
private void button1_KeyUp(object sender, KeyEventArgs e)
{
button1_KeyDown(sender, e);
}
private void button1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
MessageBox.Show("Enter key has been pressed");
}
}

Put this line soon after: InitializeComponents(); -->
button1.PreviewKeyDown +=new PreviewKeyDownEventHandler(button1_PreviewKeyDown);
.
The event you're trying to use will only fire when you focus on that button. The focus is passed in 2 different ways ( via user interaction ) one of which is an actual mouse click on that element and another is "tabbing" on to the control, and make sure you read about "Events" and "EventsHandlers"

Enter key in C#

I have a code like below
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == 13)
{
if (!textBox1.AcceptsReturn)
{
button1.PerformClick();
}
}
}
After I hit Enter, it'll send a message to another textbox and begin a new line. Can anyone help me to bring the cursor back to its first line?
I tried textBox1.SelectionStart, SelectionLength and Focus but it doesn't work, is there any another way?

You can prevent that the keypress is passed on to the control by setting the KeyPressEventArgs.Handled property to true:
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == 13)
{
if (!textBox1.AcceptsReturn)
{
button1.PerformClick();
e.Handled = true;
}
}
}
As you mentioned in a comment that you are implementing a chat app, you also might want to implement the typical behavior of Shift+Return inserting a new line:
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyValue == 13 && !e.Shift)
{
if (!textBox1.AcceptsReturn && !string.IsNullOrEmpty(textBox1.Text))
{
button1.PerformClick();
textBox1.Text = "";
e.Handled = true;
}
}
}

To set cursor position to the beginning of a textbox, use the following...
I will hazard a guess that you didn't use these in combination with each other...
textBox1.SelectionStart = 0;
textBox1.SelectionLength = 0;

How to detect if Enter was pressed in txtMessage_TextChanged() ?

I want to find out if Enter was pressed in
private void txtMessage_TextChanged(object sender, EventArgs e)
{
// do something
}
But I can't do this :
private void txtMessage_TextChanged(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
if (e.KeyChar == (char)13)
{
// Then Enter key was pressed
}
}
Since txtMessage_TextChanged doesn't have this overload .
Any suggestions ? thanks !

You need to subscribe to an event that actually captures that information.
The KeyPress event fires before TextChanged, so you could use a bool to indicate whether the Enter key was pressed.
bool enterKeyPressed = false;
private void textBox2_KeyPress(object sender, KeyPressEventArgs e)
{
enterKeyPressed = (e.KeyChar == (char)Keys.Enter);
}
private void txtMessage_TextChanged(object sender, EventArgs e)
{
if (enterKeyPressed)
{
}
}

register to this:
this.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.Login_KeyPress);
In that method set a boolean or something if keychar == 13

you can use keypress event to capture enter key event

Disable white space on key press in textbox

I am beginner in WinForms so i would like to learn that,
How can i disable white space keypress in textbox?
private void TextBox1_KeyPress(object sender, KeyPressEventArgs e)
{
// MyTextBox.Text ...?
}
Any help will be appreciated.

that's what you want, disallows all spaces
private void TextBox_KeyPress(object sender, KeyPressEventArgs e)
{
e.Handled = (e.KeyChar == (char)Keys.Space);
}

Use this code:
private void txt_keyPress(object sender, KeyPressEventArgs e) \
{
if ((sender as TextBox).SelectionStart == 0)
e.Handled = (e.KeyChar == (char)Keys.Space);
else
e.Handled = false;
}