Why Doesn\'t `addEventListener` Work for the \'copy\' Event in MSIE?

Resolving the addEventListener Issue in MSIE

In Javascript, attempting to implement the 'copy' event using addEventListener may result in the following error in MSIE:

<code class="javascript">document.getElementById('container').addEventListener('copy',beforecopy,false );
Object doesn't support this property or method</code>

Solution

MSIE diverges from the standard addEventListener approach and requires the use of 'attachEvent' instead. This can be achieved through a conditional check:

<code class="javascript">if (el.addEventListener){
  el.addEventListener('click', modifyText, false); 
} else if (el.attachEvent){
  el.attachEvent('onclick', modifyText);
}</code>

Alternatively, a custom function can be created to abstract this process:

<code class="javascript">function bindEvent(el, eventName, eventHandler) {
  if (el.addEventListener){
    el.addEventListener(eventName, eventHandler, false); 
  } else if (el.attachEvent){
    el.attachEvent('on'+eventName, eventHandler);
  }
}
//...
bindEvent(document.getElementById('myElement'), 'click', function () {
  alert('element clicked');
});</code>

Bonus: Third Parameter (useCapture)

The third argument of addEventListener ('useCapture') determines event handling precedence. If set to true, it indicates that event capturing is desired, where the event is handled at the element's ancestors before reaching the target element.

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