Windows Forms Textbox Enter key

Question

I have a TextBox, but I can't find any source explaining how to call a function when a button is pressed down.

public Simple()
{
    Text = "Server Command Line";
    Size = new Size(800, 400);

    CenterToScreen();

    Button button = new Button();
    TextBox txt = new TextBox ();

    txt.Location = new Point (20, Size.Height - 70);
    txt.Size = new Size (600, 30);
    txt.Parent = this;

    button.Text = "SEND";
    button.Size = new Size (50, 20);
    button.Location = new Point(620, Size.Height-70);
    button.Parent = this;
    button.Click += new EventHandler(Submit);
}

Some sources tell me to use a function, but I don't understand how it is going to get called.

Answer 1

If I understood correctly you want to call a method when users press Enter while typing anything in textbox? If so, you have to use the KeyUp event of TextBox like this:

public Simple()
{
    Text = "Server Command Line";
    ...

    TextBox txt = new TextBox ();
    txt.Location = new Point (20, Size.Height - 70);
    txt.Size = new Size (600, 30);
    txt.KeyUp += TextBoxKeyUp; //here we attach the event
    txt.Parent = this;    

    Button button = new Button();
    ...
}

private void TextBoxKeyUp(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.Enter)
    {
        //Do something
        e.Handled = true;
    }
}

Answer 2

you already have a button as well like this

button.Click += new EventHandler(Submit); 

if you want to call this function you can do this

button.PerformClick();  //this will call Submit you specified in the above statement