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JavaScript

Posted by John Mercer
John Mercer
31,479 Points

Prefixing JavaScript variables with "$"

When creating variables, why does Andrew create his first variable (var color) without a dollar sign, but he creates his second variable (var $newColor) with a dollar sign? What is the difference? Does "var foo" denote one thing while "var $bar" denotes something else?

1 Answer

Andrew VanVlack
Andrew VanVlack
20,155 Points

This is primarly a convetion and has no actual effect on the veriable. It is normally used to denote that the variable is a jquery object.

John Mercer
John Mercer
31,479 Points

So is 

var color = $(".selected").css("background-color");

a DOM object, whereas

var $newColor = $("<li></li>");

a jQuery object?

I have difficulty distinguishing between the two.

Andrew VanVlack
Andrew VanVlack
20,155 Points

Both of those would still be jQuery objects as they are using the jquary selectors and functions. You could use the variable $newColor in a script without any jquery and it would have no effect.

jQuery objects are just wrappers for DOM elements.