Javascript Object context - Stack Overflow

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Do this Object have its context:

{}

if yes ,than it must also have VO(Variable Object) .So than,when i do this:

foo={
    name:"Maizere",
    height:function () {console.log(name);}//output is undefined
 }

  foo.height();

When the height() method gets run js first checks function context since it can't find that name ,it travels to next i.e parent context Vo and here parent context is the context of literal object ,since that name resides in that VO why i get undefined?

How is that property residing in the VO of the literal object context simply as a property or simply like variable ,i need a plete explanation .Thank u @all.

Do this Object have its context:

{}

if yes ,than it must also have VO(Variable Object) .So than,when i do this:

foo={
    name:"Maizere",
    height:function () {console.log(name);}//output is undefined
 }

  foo.height();

When the height() method gets run js first checks function context since it can't find that name ,it travels to next i.e parent context Vo and here parent context is the context of literal object ,since that name resides in that VO why i get undefined?

How is that property residing in the VO of the literal object context simply as a property or simply like variable ,i need a plete explanation .Thank u @all.

• javascript

Share Improve this question Follow edited Aug 4, 2013 at 17:52 Maizere Pathak.Nepal asked Aug 4, 2013 at 17:46 Maizere Pathak.NepalMaizere Pathak.Nepal 2,41144 gold badges3030 silver badges4141 bronze badges 1

• When you're within the Object you have to reference the parent or self in-order to access the methods, so it would be: console.log(this.name); more information can be found over at MDN. – faino Commented Aug 4, 2013 at 17:50

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 3

You're confusing the call context (with the this keyword) with the variable scope, and with object properties.

To answer your question: No, objects do not have a scope. Only functions have a scope attribute, which will initialise the scope chain of their variable object when they get called. Since there are no variables with the name name in the scope of your height function, it resolves to undefined (or even a Reference Error).

An object member is referenced through the current object using this:

height: function() { console.log( this.name ); }
//                                ^^^^

It looks like you want the this keyword and you have a small SyntaxError on the name line (you wanted a , but wrote ;).

var foo = {
        name: "Maizere",
        height: function () {
            console.log(this.name);
        }
    };

foo.height(); // "Maizere"

Do this Object have its context:

{}

if yes ,than it must also have VO(Variable Object) .So than,when i do this:

foo={
    name:"Maizere",
    height:function () {console.log(name);}//output is undefined
 }

  foo.height();

When the height() method gets run js first checks function context since it can't find that name ,it travels to next i.e parent context Vo and here parent context is the context of literal object ,since that name resides in that VO why i get undefined?

How is that property residing in the VO of the literal object context simply as a property or simply like variable ,i need a plete explanation .Thank u @all.

Do this Object have its context:

{}

if yes ,than it must also have VO(Variable Object) .So than,when i do this:

foo={
    name:"Maizere",
    height:function () {console.log(name);}//output is undefined
 }

  foo.height();

When the height() method gets run js first checks function context since it can't find that name ,it travels to next i.e parent context Vo and here parent context is the context of literal object ,since that name resides in that VO why i get undefined?

How is that property residing in the VO of the literal object context simply as a property or simply like variable ,i need a plete explanation .Thank u @all.

• javascript

Share Improve this question Follow edited Aug 4, 2013 at 17:52 Maizere Pathak.Nepal asked Aug 4, 2013 at 17:46 Maizere Pathak.NepalMaizere Pathak.Nepal 2,41144 gold badges3030 silver badges4141 bronze badges 1

• When you're within the Object you have to reference the parent or self in-order to access the methods, so it would be: console.log(this.name); more information can be found over at MDN. – faino Commented Aug 4, 2013 at 17:50

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 3

You're confusing the call context (with the this keyword) with the variable scope, and with object properties.

To answer your question: No, objects do not have a scope. Only functions have a scope attribute, which will initialise the scope chain of their variable object when they get called. Since there are no variables with the name name in the scope of your height function, it resolves to undefined (or even a Reference Error).

An object member is referenced through the current object using this:

height: function() { console.log( this.name ); }
//                                ^^^^

It looks like you want the this keyword and you have a small SyntaxError on the name line (you wanted a , but wrote ;).

var foo = {
        name: "Maizere",
        height: function () {
            console.log(this.name);
        }
    };

foo.height(); // "Maizere"

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