The simplest use of bind()
is to make a function that, no matter
how it is called, is called with a particular this
value.
x = 9;
var module = {
x: 81,
getX: function () {
return this.x;
}
};
module.getX(); // 81
var getX = module.getX;
getX(); // 9, because in this case, "this" refers to the global object
// create a new function with 'this' bound to module
var boundGetX = getX.bind(module);
boundGetX(); // 81
Please refer this link for more information
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind