Question

I want to access an object’s own function from a jQuery method which fails.

function obj(){    
    this.send = function(){
        $.get("send.php",null,function(data){
            this.success();
        }).error(function(){ this.fail(); });
    }
    this.fail = function(){
        alert("fail");
    }
}

var o = new obj();
o.send();

Gives this error: TypeError: this.fail is not a function

How to access function fail inside jQuery?

Answer 1

On line 5, failis not called by the same object, so thisdoes not have the same reference, and therefore no method fail. We say that you change context.

The trick is to use a variable often called self or that or _this. I prefer self.

function obj(){    
    var self = this;
    this.send = function(){
        $.get("send.php",null,function(data){
            this.success();
        }).error(function(){ self.fail(); });
    }
    this.fail = function(){
        alert("fail");
    }
}

It should make it, and yes, javascript looks like a pity language. But once you overcome the few problems, you will love the possibilities.