How to add an onchange event to a select box via javascript?

问题

I've got a script where I am dynamically creating select boxes. When those boxes are created, we want to set the onchange event for the new box to point to a function called toggleSelect().

I can't seem to get the syntax right to create the onchange event. Can someone tell me what I'm doing wrong? It doesn't throw an error, but doesn't work, either.

  col = dataRow.insertCell(0);
  var transport_select = document.createElement('select');
  transport_select.id = transport_select_id;
  transport_select.options[0] = new Option('LTL', 'LTL');
  transport_select.options[1] = new Option('FTL', 'FTL');
  transport_select.onChange = function(){toggleSelect(transport_select_id);};
  col.appendChild(transport_select);

回答1:

Add

transport_select.setAttribute("onchange", function(){toggleSelect(transport_select_id);});

setAttribute

or try replacing onChange with onchange

回答2:

Here's another way of attaching the event based on W3C DOM Level 2 Events Specification:

  transport_select.addEventListener(
     'change',
     function() { toggleSelect(this.id); },
     false
  );

回答3:

replace:

transport_select.onChange = function(){toggleSelect(transport_select_id);};

with:

transport_select.onchange = function(){toggleSelect(transport_select_id);};

on'C'hange >> on'c'hange

You can use addEventListener too.

回答4:

If you are using prototype.js then you can do this:

transport_select.observe('change', function(){
  toggleSelect(transport_select_id)
})

This eliminate (as hope) the problem in cross-browsers

来源：https://stackoverflow.com/questions/1628826/how-to-add-an-onchange-event-to-a-select-box-via-javascript

标签

javascript

javascript-events