Javascript setInterval and `this` solution

Question

I need to access this from my setInterval handler

prefs: null,
startup : function()
    {
        // init prefs
        ...
                


        

Answer 1

this.intervalID = setInterval(this.retrieve_rate.bind(this), this.INTERVAL);

Answer 2

This would be the cleanest solution, since most of the time you actually want to switch the this context for your consecutive method calls:

Also it's easier to grasp the concept of.

    // store scope reference for our delegating method
    var that = this;
    setInterval(function() {
        // this would be changed here because of method scope, 
        // but we still have a reference to that
        OURMETHODNAME.call(that);
    }, 200);

Answer 3

That's not a beauty solution but it's in common usage:

var self = this;
var ajax = null;
//...
ajax.onload = function() {
    self.prefs....;
}