HTML Text Input: Avoid submit when enter is pressed

Using jQuery:

<script>
  $('#first_page').keypress(function(e) {
    if (e.keyCode == '13') {
      e.preventDefault();
      //your code here
    }
  });​
</script>

using javascript

<input type="text" id="first_page" onPaste="" onkeydown="if (event.keyCode == 13) { alert('enter');return false;}" />