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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"

How to run event implementation from other event condition

I'm wondering, if is it possible to run if (e.KeyCode == Keys.Enter) event process without pressing on enter, correctly to say without event condition itself.
The only way I know to get result, which can be useful if implemented, is to locate content of condition in function, but I'm asking if it is possible other way.
From textBox2_TextChanged event condition to get implementation of if (e.KeyCode == Keys.Enter) event of textBox1_KeyDown with entering of exist text and containing process implementation?
For example:
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
/// code
if (e.KeyCode == Keys.Enter)
{
label1.Text = ("text inserted");
}
}
and desired result is to call (e.KeyCode == Keys.Enter) implementation with label1.Text = ("text inserted"); from textBox1_KeyDown in textBox2_TextChanged here:
private void textBox2_TextChanged(object sender, EventArgs e)
{
if (x > 0)
{
/// here I want implement if (e.KeyCode == Keys.Enter) from code above with label1.Text = ("text inserted");
}
}

you can like this
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
label1.Text = ("text inserted");
}
}
private void textBox2_TextChanged(object sender, EventArgs e)
{
KeyEventArgs ev = new KeyEventArgs(Keys.Enter);
textBox1_KeyDown(sender, ev);
}

C# - How can I block the typing of a letter on a key press?

I have a textbox with a OnKeyPress event. In this textbox I wish to input only numbers, and for some specific letters like t or m, I would want to execute a code without that letter being typed in the textbox. Small sample of what I am trying to do:
//OnKeyPressed:
void TextBox1KeyDown(object sender, KeyEventArgs e)
{
if(e.KeyCode == Keys.T || e.KeyCode == Keys.M) Button1Click(this, EventArgs.Empty);
}
This unfortunately does not prevent the input of the letter..

Set the SuppressKeyPress property from KeyEventArgs to true, like below:
private void TextBox1KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.T || e.KeyCode == Keys.M)
{
e.SuppressKeyPress = true;
Button1Click(this, EventArgs.Empty);
}
}

You could always run the TryParse on the keyDown event so as to validate as the data gets entered. It saves the user an additional UI interaction.
private void TextBox1KeyDown(object sender, KeyEventArgs e)
{
int i;
string s = string.Empty;
s += (char)e.KeyValue;
if (!(int.TryParse(s, out i)))
{
e.SuppressKeyPress = true;
}
else if(e.KeyCode == Keys.T || e.KeyCode == Keys.M)
{
e.SuppressKeyPress = true;
Button1Click(this, EventArgs.Empty);
}
}

Save a text string to textbox with keyboard shortcut

Im a beginner in C# and im trying to create a windows form application that save a copied text to a textbox when you execute a command with the keyboard. I know there is mouch more to do but where do i start? I suceed to make someting happening with the code below a start at least..
And another question.. is it possible to create more than 2 commands. It doesn't work if i add for example : " && KeyCode.ToString() == "B") "
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if (e.Control && e.KeyCode.ToString() == "C")
{
MessageBox.Show("CTRL+C");
}
}
Cheers

You would manage this by calling keyDown/Up events. Keep track of each event and which key went down. Then using the Clipboard.GetText() function to copy/paste the text from clipboard into your textbox once both keys are down.
Example,
bool keyup = false;
bool keyleft = false;
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Up)
{
keyup = true;
}
else if (e.KeyCode == Keys.Left)
{
keyleft = true;
}
if (keyleft && keyup)
{
textboxOne.Text = Clipboard.GetText(TextDataFormat.Html);
}
}
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Up)
{
keyup = false;
}
else if (e.KeyCode == Keys.Left)
{
keyleft = false;
}
}
Used both these as my resources.
Resource One: Detect when two keys are pressed at the same time
Resource Two: http://msdn.microsoft.com/en-us/library/c2thcsx4%28v=vs.110%29.aspx

Register Modifier keys for a CustomControl

I am working on a CustomControl and I want to register ModifierKeys in this control. I have already set the KeyPerview to True in the Form which this control is being added to.
Now I have a Boolean named _ctrl and I want this boolean to be true when the Control key is being held down and it should be false when Control key is being released.
I tried to achive this with the conde belowe in my CustomControl but no success!
private bool _ctrl = false;
private void MyCustomControl_KeyDown(object sender, KeyEventArgs e)
{
if(e.KeyCode == Keys.Control)
{
_ctrl = true;
}
}
private void MyCustomControl_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Control)
{
_ctrl = false;
}
}
Any tips/soloution will be appriciated!
UPDATE
Ok, I decided to do the key down and up event in the form itself:
private void MainForm_KeyDown(object sender, KeyEventArgs e)
{
if (e.Modifiers == Keys.Control)
{
projectBrowser.ControlKeyIsDown = true; //bool in MyCustomControl
MessageBox.Show("CTRL is PRESSED");
}
}
private void MainForm_KeyUp(object sender, KeyEventArgs e)
{
if (e.Modifiers == Keys.Control)
{
projectBrowser.ControlKeyIsDown = false; //bool in MyCustomControl
MessageBox.Show("CTRL is DEPRESSED");
}
}
Now, The KeyDown event detects the control key and messagebox is being shown. But the KeyUp event does not work and it doesn't show the messagebox. What could be wrong?
It seems that the key up gets detected if I change the KeyUpevent like this:
private void MainForm_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.LControlKey || e.KeyCode == Keys.RControlKey || e.KeyCode == Keys.ControlKey || e.KeyCode == Keys.Control)
{
projectBrowser.ControlKeyIsDown = false;
e.Handled = true;
}
}

You can try calling the Control.ModifierKeys property:
protected override void OnKeyDown(KeyEventArgs e) {
if (Control.ModifierKeys == Keys.Control) {
MessageBox.Show("I am pressing control.");
}
base.OnKeyDown(e);
}
If you throw up a MessageBox on the KeyDown event, the KeyUp event won't get called.