javascript - How to create a reference to an anonymouse addEventListener handler? - 


function alertstring(str) {     alert(str); }  var str = "hello"; var alert_string = document.getelementbyid("alert_str");  // can removed removeeventlistener // alert_str.addeventlistener("click", alertstring, false);  // since need pass argument // alertstring wrapped within anonymouse function alert_string.addeventlistener("click", function() {     alertstring(str); }, false);  document.getelementbyid("remove_alert").onclick = function() {     alert_string.removeeventlistener("click", alertstring, false); }; 
<input type="button" id="alert_str" value="alert" /> <input type="button" id="remove_alert" value="remove alert" />

the click event handler cannot removed since wrapped inside anonymouse function.

how can create reference function can remove alertstring alert button?

quickest, simplest method:

function alertstringwrapper() {     alertstring(str); } alert_string.addeventlistener("click", alertstringwrapper, false);

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