title: How to validate only number in winform?
body: <p>How to validate for numbers without using keypress option
  why isnt <code>Char.IsNumber</code> or <code>.IsDigit</code> working
  or should I use regex expression for validation  </p>
  
  <pre><code>private bool ValidateContact()
  {
      if (Char.IsNumber(textBox4.Text)){
          return true;
  }
  </code></pre>