javascript

Chapter 12: Events
Property/Method Type Read/Write Description
bubbles Boolean Read only Indicates if the event bubbles.
cancelable Boolean Read only Indicates if the default behavior of the event
can be canceled.
currentTarget Element Read only The element whose event handler is
currently handling the event.
detail Integer Read only Extra information related to the event.
eventPhase Integer Read only The phase during which the event handler
is being called: 1 for the capturing phase, 2
for “ at target, ” and 3 for bubbling.
preventDefault() Function Read only Cancels the default behavior for the event.
If cancelable is true , this method can be
used.
stopPropagation() Function Read only Cancels any further event capturing or
event bubbling. If bubbles is true , this
method can be used.
target Element Read only The target of the event.
type String Read only The type of event that was fired.
view AbstractView Read only The abstract view associated with the event.
This is equal to the window object in which
the event occurred.
Inside an event handler, the this object is always equal to the value of currentTarget , whereas
target contains only the actual target of the event. If the event handler is assigned directly onto the
intended target, then this , currentTarget , and target all have the same value. Here is an example:
var btn = document.getElementById(“myBtn”);
btn.onclick = function(event){
alert(event.currentTarget === this); //true
alert(event.target === this);
//true
};
This code examines the values of currentTarget and target relative to this . Since the target of the
click event is the button, all three are equal. If the event handler existed on a parent node of the button,
such as document.body , the values would be different. Consider the following example:
document.body.onclick = function(event){
alert(event.currentTarget === document.body); //true
alert(this === document.body);
//true
alert(event.target === document.getElementById(“myBtn”)); //true
};
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