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JavaScript

Posted by Daniele Vicinanzo
Daniele Vicinanzo
21,277 Points

difference between var variable = "variable"; and var $variable = "variable";

I don't understood the difference between var variable = "variable"; and var $variable = "variable"; in jquery

I got just that it is a convenction used to recognize objects but I'm a bit confused about it

I also confuse var variable = "<p>hello</p>"; with var variable = $("<p>hello</p>");

why put the $() before the value of a variable to put inside it?

3 Answers

Jacob Mishkin
Jacob Mishkin
23,118 Points
Jacob Mishkin
Jacob Mishkin
23,118 Points

The difference is you have two variables. One called variable and one called $variable, and in your example they equal the same thing.

They are two different variable names.

for more info please see this link:

stackoverflow

Jacob Mishkin
Jacob Mishkin
23,118 Points

"I also confuse var variable = "hello"; with var variable = $("hello");"

the difference between theses two is:

var variable = "hello" equals the string Hello

var variable = $("hello") equals the reference to a Jquery object called hello.

Daniele Vicinanzo
Daniele Vicinanzo
21,277 Points
Daniele Vicinanzo
Daniele Vicinanzo
21,277 Points

yes ok, I got the two differences but I cannot peek the real difference of the last why a string is not the same thing of a jquery object with a string inside?? there is a difference in the behavior??

ps the post wrote wrong, I wrote $(""); with inside a paragraph with inside "hello"

Jacob Mishkin
Jacob Mishkin
23,118 Points

"In the first formulation listed above, jQuery() — which can also be written as $() — searches through the DOM for any elements that match the provided selector and creates a new jQuery object that references these elements:"

"Creating New Elements

If a string is passed as the parameter to $(), jQuery examines the string to see if it looks like HTML (i.e., it starts with <tag ... >). If not, the string is interpreted as a selector expression, as explained above. But if the string appears to be an HTML snippet, jQuery attempts to create new DOM elements as described by the HTML. Then a jQuery object is created and returned that refers to these elements. You can perform any of the usual jQuery methods on this object"

this is taken from the Jquery documentation. I hope this clears up some confusion.

Daniele Vicinanzo
Daniele Vicinanzo
21,277 Points
Daniele Vicinanzo
Daniele Vicinanzo
21,277 Points

thanks