Thread: Replacing character is character is different

Replacing character if character is different

Hi guys, im new here..

I am doing a wireless transmission with C#.

i am now using a textbox, with a max length of 1.
example upon running the program, i press A. And when I press B, it produces a sound "ding", which i believe that it tells me that the length is full, i have to backspace it and retype the B.

How can I type this program so that like first I type A, it shows A in the textbox.
and if the next moment i type something different, it shows the new character, replacing the new one. but if its the same, the old character remains..

Thanks in advance..

How about something like this?

Code:

    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            TextBox textbox = new TextBox();
            textbox.Location = new Point(0, 0);
            textbox.MaxLength = 1;
            textbox.KeyDown += new KeyEventHandler(textbox_KeyDown);
            Controls.Add(textbox);
        }

        void textbox_KeyDown(object sender, KeyEventArgs e)
        {
            if (!Char.IsControl((char)e.KeyCode))
                (sender as TextBox).Text = "";
        }
    }