title: event is not defined in mozilla firefox for javascript function?
body: <pre><code>function onlyNumeric() {   
      if (event.keyCode &lt; 48 || event.keyCode &gt; 57) {
          event.returnValue = false; 
      }
  
  }
  
  onkeypress=onlyNumneric();
  </code></pre>
  
  <p>In IE, this code is working fine. However, in Mozilla Firefox, the event is an undefined error.</p>