<html>
<head>
  <title> Submit08 </title>
  <script language="javascript">
    /* Ver en: http://www.webintenta.com/
                      validacion-con-expresiones-regulares-y-javascript.html
     */
    function enviar()
    {
      erNick = /[a-zA-Z0-9]{2,16}/ /* equivalente a /[\w_-]{2,16}/ */
      erMail = /[\w-\.]{3,}@([\w-]{2,}\.)*([\w-]{2,}\.)[\w-]{2,4}/
      cNick = document.getElementById("nick")
      cMail = document.getElementById("email")
      if (!cNick.value.match (erNick)) {
        alert("Nick incorrecto!");
        cNick.focus();
        cNick.select();
      }
      else if (!cMail.value.match (erMail)) {
        alert("Email incorrecto!");
        cMail.focus();
        cMail.select();
      }
      else
        document.formulario.submit()
    }
  </script>
</head>

<body>
  <form name="formulario" target="_top" method="get">
    Nick: <input id="nick"   name=nick  type="text" size="16" />   <br />
    Email: <input id="email" name=email type="text" size="32" /> <br />
    <input type="button" value="Enviar" onclick="enviar()" /></td>
  </form>
</body>
</html>