JavaScript AddEventListener third parameter function

Dom Methods AddEventListener () and RemoveEventListener () are functions that are used to assign and delete events. Both of these methods require three parameters, respectively:

The event name (String), the event handler function (function) to fire, the period or phase (Boolean) that specifies the event handler.

<!--open a new browser window--><button id= "new" onclick= "" "> click Pop-up </button><!--close a newer browser window--><button id=" Old "onclick=" "> Click Close Window </button>
<script>//     Open a new browser window    document.getElementById ("new"). AddEventListener ("click", function () {        window.open ("http://baidu.com", "Windows-name", "height=500,width=800, top=200,left=200 toolbar= No, Meubar=yes ");    });
//     Close the new browser window     document.getElementById ("old"). AddEventListener ("click",  function() {        window.close ();    }); </script>

　　

Dom Event flow (cut from JavaScript advanced programming, lazy painting):

The image shows that the capture process precedes the bubbling process

When the third parameter is set to True, it is executed during the capture process, and the handler function is executed during the bubbling process.

JavaScript AddEventListener third parameter function