this vs $(this) [duplicate]
Possible Duplicate:
jQuery $(this) vs this
I'm new to this and trying to get my concept right. There has been many instances of the use of "this
" and "$(this)
". Can someone please explain the difference and in what condition that we use the t开发者_如何学Gowo different "this"?
In jQuery functions, this
most often refers to the actual DOM element you're dealing with, whereas $(this)
returns a jQuery object that wraps the element.
In JavaScript, this
always refers to the current scope. Many of jQuery's functions will set that scope to be the element you're working with.
For instance
$("#someElement").click(function() {
this; // the element itself
$(this); // a jQuery wrapper-object around the element
});
The point is, that the jQuery object has all the jQuery functions (like .detatch()
or .prependTo()
etc.), while the DOM element is what the browser provides. In the example above, the element would be exactly the same as what you'd get, if you called document.getElementById("someElement")
$(this)
refers to a jquery object, this
refers to this
in the current scope
$(this)
is a jQuery object. this
refers to the value of this
within the current scope. You typically use $(this)
inside a callback when you want to convert the element that triggered the event, into a jQuery object. You can do this to pretty much any DOM element, so $(document.getElementById("#myElement"))
is also valid, and is a jQuery object that represents the DOM element with id "myElement".
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