title: Disable number input in a text input with js
body: <p>What I have to do is not permit to introduce number characters in a text input in a form, but I've to do it with javascript. Here's my HTML code:</p>
  
  <pre><code>&lt;form id="formu"&gt;
  &lt;input type="text" id="num" /&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>And here's my JS code:</p>
  
  <pre><code>function numero(theEvent){
  
      var evento=theEvent||window.event;
  
          switch(evento.type){
              case 'keypress':
                  if(document.getElementById("num").evento.keyCode&gt;=48&amp;&amp;document.getElementById("num").evento.keyCode&lt;=57){
                      return false;
                  }
          }
      }
  </code></pre>