Accessing class member variables inside an event handler in Javascript

Question

I have a quick question regarding the proper way to access Javascript class member variables from inside of an event handler that class uses. For example:

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Answer 1

Since this changes in an event context (points to global usually), you need to store a reference to yourself outside of the event:

function Map() {
    this.x = 0;
    this.y = 0;
    var _self = this;
    $("body").mousemove( function(event) {
        _self.x = event.pageX;     // Is now able to access Map's member variable "x"
        _self.y = event.pageY;     // Is now able to access Map's member variable "y"
    });
}