Use of the JavaScript 'bind' method -

what use of bind() in javascript?

bind creates new function have this set first parameter passed bind().

here's example shows how use bind pass member method around has correct this:

var button = function(content) {    this.content = content; }; button.prototype.click = function() {   console.log(this.content + ' clicked'); }  var mybutton = new button('ok'); mybutton.click();  var looseclick = mybutton.click; looseclick(); // not bound, 'this' not mybutton - global object  var boundclick = mybutton.click.bind(mybutton); boundclick(); // bound, 'this' mybutton 

which prints out:

ok clicked undefined clicked ok clicked 

you can add parameters after 1st (this) parameter , bind pass in values original function. additional parameters later pass bound function passed in after bound parameters:

// example showing binding parameters var sum = function(a, b) {   return + b; };  var add5 = sum.bind(null, 5); console.log(add5(10)); 

which prints out:

15 

check out javascript function bind more info , interactive examples.