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..

Capture the textbox's OnKeyDown event.

hi.. can i teach me how do i do that?

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 = "";
        }
    }

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Quote:

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Originally Posted by itsme86

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 = "";
        }
    }

---

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HEY! a million thanks!