I have this example code:
var foo = {
self: this,
init: function(){
self.doStuff();
},
doStuff: function(){
alert(\'doing
Because at the time you declare the object literal this
is not a reference to the object, but to whatever the calling context is.
ES6 provides getters for the object properties, so you can use them to reference the object itself and to use its other members:
var foo = {
prop1: 1,
get prop2() { return this.prop1 + 1; }
}
// foo.prop2 = 2;
The value of this
is determined by how the current function was called. It does not refer to the current object.
This will work:
var foo = {
init: function(){
this.doStuff();
},
doStuff: function(){
alert('doing stuff');
}
};
foo.init();
Since when you call foo
.init()
, this
becomes foo
.
Following up on Qeuntin's response you would use the following to achieve what you're looking for
var foo = {
self: false,
init: function(){
self = this
self.doStuff();
},
doStuff: function(){
alert('doing stuff');
},
}
EDIT: Since it's been pointed out that whilst this solves OP's problem (i.e it works) it isn't exactly how you should go about it. So, here's a scoping reference.
function A()
{
//Semi-private / hidden var
var pVar = "I'm a private, err hidden, variable",
//fn (technically a var)
pFn = function(){},
//empty var, placholder for hidden fn
privatePlaceholderFn;
//Instance-time... public fn
this.instancePublicFn = function()
{
console.log("--- instace public ---");
//Print hidden var to cosole
console.log(pVar);
//Call hidden fn
instancePrivateFn();
console.log("--->Setting private from instance public")
//Set the hidden fn
setPrivate();
console.log("--- / instance public ---");
}
//Pass fn to private method.
this.setPrivFromOutside = function(fn)
{
setPrivateFromPrivateYetOutside(fn);
}
//Set the hidden fn
this.iPFnPlaceholderSetter = function(fn)
{
privatePlaceholderFn = fn;
}
//Call the semi-private / hidden fn
this.callPrivate = function()
{
privatePlaceholderFn();
}
//A misnomer, proves the scope exists. See "function setPrivate()"
this.setPrivateFromInstance = function()
{
//Prove scope exists
console.log(privatePlaceholderFn);
console.log("Private From instance - gets inside scope");
}
//Set hidden fn from private method
function setPrivate()
{
privatePlaceholderFn = function()
{
//Show scope exists
console.log(pVar);
}
}
//Set the hidden fn from hidden method
function setPrivateFromPrivateYetOutside(fn)
{
//fn's scope won't resolve to inside
privatePlaceholderFn = fn;
}
//Private / hidden messager
function instancePrivateFn()
{
//Just loggin' something
console.log("Instance Private method");
}
}
//Add an object method to the prototype
A.prototype.protoPuFn = function(){
console.log("---> Private var from object literal method");
//console.log(pVar)
}
//...
a = new A();
//Add object literal fn
a.objFn = function()
{
console.log("Object literal defined public fn - Gets outside scope");
//console.log(pVar);
}
//Set private / hidden placeholder fn
a.iPFnPlaceholderSetter(function()
{
console.log("Hidden fn, passed through instance public - gets outside scope");
//console.log(pVar);
});
//Attempt to read hidden var
console.log(a.pVar);
//Call object literal defined fn
a.objFn();
//Call the hidden fn
a.callPrivate();
//Call prototype added fn
a.protoPuFn();
//Call instance added public fn
a.instancePublicFn();
//Call private / hidden method (set
a.callPrivate();
//Same as iPFnPlaceholderSetter except the param is passed to a hidden method, before seting.
a.setPrivFromOutside(function()
{
console.log("-->Passed from outside, through public then private setters");
//console.log(pVar)
})
//Call the hidden method
a.callPrivate();
//Set hidden fn from instance public
a.setPrivateFromInstance();
//Call the hidden method.
a.callPrivate();
//Use evi(a)l fn to steal scope.
a.evil("this.meth = function(){console.log(pVar)}");
//Call fn with stolen scope
a.meth();