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Marc-Oliver Gern
8,747 PointsWhen to use $ sign for a variable name?
In his jQuery Basics, Andrew sometimes uses a $ sign to start a variable name. For example:
var $canvas = $("canvas");
What is the reason for that? Does anybody know?
3 Answers
Daryl Carr
18,318 PointsIt's basically to differentiate between a something that is wrapped in jQuery and something that isn't. For example, something that is wrapped in jquery you could then call another jQuery method on whereas a normal javascript variable can be used to refer to just an element that isn't wrapped in jQuery and so you wouldn't be able to call a jQuery method on it
Jacob Bergdahl
29,119 PointsHe explained it when he first used it :) He uses that prefix to show that it's a jQuery representation of an object.
Marc-Oliver Gern
8,747 PointsThanks for the replies. That really helped. It was just confusing since Andrew didn't do it on, color and context:
var color = $(".selected").css("background-color"); var $canvas = $("canvas"); var context = $canvas[0].getContext("2d"); var lastEvent;