Get the name of [object Object] using 'this'

Question

I´m working with a software where I don't know the global object name(no, it´s not window), but I want to.

console.log(this)

gives me [object object]

for(var property in this) {
    console.log(property + "=" + this.property);
}

gives me the properties of 'this'.

However, I need the name/id(something with what I could access the properties in another contexts/objects) of 'this'. Is it somehow possible to get that?

I already searched for this, but couldn´t find a fitting solution.

@Liam they do if they are created using a Constructor function or the new ES6 class syntax. — WilomGfx, May 17 '17 at 12:58
@FelixKling i am aware of that, but an object created from a Constructor or the new ES6 class syntax will. — WilomGfx, May 17 '17 at 13:00
@WilomGfx: Can you link to the spec where this is described? — Felix Kling, May 17 '17 at 13:01
Objects don't have "names". `a = {}; b = a;` Is this object's "name" a or b? Anyway, you can use `this.prop` or `this['prop']` and you can assign the value of `this` like any other variable `thing = this; thing.prop = something` — John Hascall, May 17 '17 at 13:02
@FelixKling Thanks, that´s a nice workaround. Didn´t think of that. — Faizy, May 17 '17 at 13:02

Pranav C Balan · Accepted Answer · 2017-05-17T13:20:21.243

4

You need to get the property value from this context using bracket notation.

for(property in this) {
    console.log(property + "=" + this[property]);
    //                       ----^^^^^^^^^^^^^^----
}

You can get the object properties using Object.keys method which returns the array of property names.

FYI : To access this context within an another context refers it using a variable which has scope within both contexts(commonly you can use a global variable).

// initial variable or neglect to make it as global
var self;

/* cotext 1 start */

// define   
self = this;

for(property in self) {
    console.log(property + "=" + self[property]);
}
/* cotext 1 end  */

/* cotext 2 start */

// use `self` to refer the context1         
for(property in self) {
    console.log(property + "=" + self[property]);
} 

/* cotext 2 end  */

edited May 17 '17 at 13:20

answered May 17 '17 at 12:56

Pranav C Balan

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Also, a bad alternative is `JSON.stringify`. Or `console.log("%O", this);` or `console.log("%o", this);`. – Ismael Miguel May 17 '17 at 13:00
1

Sorry, i meant it like the way you wrote it. My mistake. Thank you. – Faizy May 17 '17 at 13:00
While this clearly a mistake in the OP's code, I don't think that's what they are asking about. – Felix Kling May 17 '17 at 13:05

Get the name of [object Object] using 'this'

1 Answers1