JS element event bindings and unbinding

There are 3 ways to bind an event to an element:

1, the most common way of binding:

document.getElementById ("Btn"). onclick=function() {};

2, non-IE browser element.addeventlistener (type,fn,false)

(Boolean ====true means capture, false means bubbling, usually false):

document.getElementById ("Btn"). AddEventListener ("click", Function () {};false);

3,IE browser event binding element.attachevent ("on" +TYPE,FN)

document.getElementById ("Btn"). Attachevent ("onclick",function() {});

================== compatible code for element binding events: =======================

1     function AddEventListener (ELEMENT,TYPE,FN) {2                 if (element.addeventlistener) {3                     Element.addeventlistener (Type,fn,false); 4                 }else if (element.attachevent) {5                     element.attachevent ("on" +TYPE,FN), 6                 }else{7                     element["on" +type ]=FN; 8                 } 9             }

There are 3 ways to unbind an element:

1, Ordinary way:

document.getElementById ("Btn"). Onclick=null;

2, non-IE browser element.removeeventlistener (type,fname,false)

(Boolean ====true means capture, false means bubbling, usually false):

document.getElementById ("Btn"). RemoveEventListener ("click", Fname,false);

3,IE browser element.detachevent ("on" +type,fname)

document.getElementById ("Btn"). DetachEvent ("onclick", fName);

================== compatible code for an element to unbind an event: =======================

1     functionRemoveEventListener (element,type,fname) {2                 if(element.removeeventlistener) {3Element.removeeventlistener (Type,fname,false);4}Else if(element.detachevent) {5Element.detachevent ("on" +type,fname);6}Else{7element["on" +type]=NULL;8                 }9             } 

JS element event bindings and unbinding