How do I make a textbox that only accepts numbers?

Question

I have a windows forms app with a textbox control that I want to only accept integer values. In the past I\'ve done this kind of validation by overloading the KeyPress event

Answer 1

Hi you can do something like this in the textchanged event of the textbox.

here is a demo

    private void textBox1_TextChanged(object sender, EventArgs e)
    {
        string actualdata = string.Empty;
        char[] entereddata = textBox1.Text.ToCharArray();
        foreach (char aChar in entereddata.AsEnumerable())
        {
            if (Char.IsDigit(aChar))
            {
                actualdata = actualdata + aChar;
                // MessageBox.Show(aChar.ToString());
            }
            else
            {
                MessageBox.Show(aChar + " is not numeric");
                actualdata.Replace(aChar, ' ');
                actualdata.Trim();
            }
        }
        textBox1.Text = actualdata;
    }