I am having problem understanding the behavior of below code in JavaScript Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern) Data science time! April 2019 and salary with experience The Ask Question Wizard is Live!Convert character to ASCII code in JavaScriptInvoking JavaScript code in an iframe from the parent pageHow to execute a JavaScript function when I have its name as a stringHow to find event listeners on a DOM node when debugging or from the JavaScript code?Simplest code for array intersection in javascriptDoes JavaScript have a method like “range()” to generate a range within the supplied bounds?How to set a JavaScript breakpoint from code in Chrome?Can't access object property, even though it exists. Returns undefinedDoes Javascript writable descriptor prevent changes on instances?Can't define set and get methods

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I am having problem understanding the behavior of below code in JavaScript



Announcing the arrival of Valued Associate #679: Cesar Manara
Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern)
Data science time! April 2019 and salary with experience
The Ask Question Wizard is Live!Convert character to ASCII code in JavaScriptInvoking JavaScript code in an iframe from the parent pageHow to execute a JavaScript function when I have its name as a stringHow to find event listeners on a DOM node when debugging or from the JavaScript code?Simplest code for array intersection in javascriptDoes JavaScript have a method like “range()” to generate a range within the supplied bounds?How to set a JavaScript breakpoint from code in Chrome?Can't access object property, even though it exists. Returns undefinedDoes Javascript writable descriptor prevent changes on instances?Can't define set and get methods



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8















I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct



When I debug the code and evaluate the profile I can see the name & age property in the object
But at the time of output, it only shows the name property






//Code Snippet 
let profile =
name: 'Barry Allen',


// I added a new property in the profile object.
Object.defineProperty(profile, 'age',
value: 23,
writable: true
)

console.log(profile)
console.log(profile.age)





Now expected output here should be



name: "Barry Allen", age: 23
23


but I get the output as.
Note that I am able to access the age property defined afterwards.
I am not sure why the console.log() is behaving this way.



name: "Barry Allen"
23









share|improve this question









New contributor




Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.


























    8















    I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct



    When I debug the code and evaluate the profile I can see the name & age property in the object
    But at the time of output, it only shows the name property






    //Code Snippet 
    let profile =
    name: 'Barry Allen',


    // I added a new property in the profile object.
    Object.defineProperty(profile, 'age',
    value: 23,
    writable: true
    )

    console.log(profile)
    console.log(profile.age)





    Now expected output here should be



    name: "Barry Allen", age: 23
    23


    but I get the output as.
    Note that I am able to access the age property defined afterwards.
    I am not sure why the console.log() is behaving this way.



    name: "Barry Allen"
    23









    share|improve this question









    New contributor




    Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.






















      8












      8








      8








      I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct



      When I debug the code and evaluate the profile I can see the name & age property in the object
      But at the time of output, it only shows the name property






      //Code Snippet 
      let profile =
      name: 'Barry Allen',


      // I added a new property in the profile object.
      Object.defineProperty(profile, 'age',
      value: 23,
      writable: true
      )

      console.log(profile)
      console.log(profile.age)





      Now expected output here should be



      name: "Barry Allen", age: 23
      23


      but I get the output as.
      Note that I am able to access the age property defined afterwards.
      I am not sure why the console.log() is behaving this way.



      name: "Barry Allen"
      23









      share|improve this question









      New contributor




      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct



      When I debug the code and evaluate the profile I can see the name & age property in the object
      But at the time of output, it only shows the name property






      //Code Snippet 
      let profile =
      name: 'Barry Allen',


      // I added a new property in the profile object.
      Object.defineProperty(profile, 'age',
      value: 23,
      writable: true
      )

      console.log(profile)
      console.log(profile.age)





      Now expected output here should be



      name: "Barry Allen", age: 23
      23


      but I get the output as.
      Note that I am able to access the age property defined afterwards.
      I am not sure why the console.log() is behaving this way.



      name: "Barry Allen"
      23





      //Code Snippet 
      let profile =
      name: 'Barry Allen',


      // I added a new property in the profile object.
      Object.defineProperty(profile, 'age',
      value: 23,
      writable: true
      )

      console.log(profile)
      console.log(profile.age)





      //Code Snippet 
      let profile =
      name: 'Barry Allen',


      // I added a new property in the profile object.
      Object.defineProperty(profile, 'age',
      value: 23,
      writable: true
      )

      console.log(profile)
      console.log(profile.age)






      javascript






      share|improve this question









      New contributor




      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question









      New contributor




      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|improve this question




      share|improve this question








      edited 1 hour ago









      Eddie

      20.3k51642




      20.3k51642






      New contributor




      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked 1 hour ago









      Ravi WRavi W

      434




      434




      New contributor




      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






















          3 Answers
          3






          active

          oldest

          votes


















          9














          You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.




          enumerable

          true if and only if this property shows up during enumeration of the properties on the corresponding object.
          Defaults to false.




          Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console






          let profile = 
          name: 'Barry Allen',


          // I added a new property in the profile object.

          Object.defineProperty(profile , 'age',
          value: 23,
          writable: true,
          enumerable: true
          )
          console.log(profile)
          console.log(profile.age)





          All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.



          To get all properties(including non-enumerable)Object​.get​OwnProperty​Names()
          .






          let profile = 
          name: 'Barry Allen',


          // I added a new property in the profile object.

          Object.defineProperty(profile , 'age',
          value: 23,
          writable: true,
          enumerable: false
          )
          for(let key in profile) console.log(key) //only name will be displayed.

          console.log(Object.getOwnPropertyNames(profile)) //You will se age too








          share|improve this answer

























          • I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

            – randomSoul
            1 hour ago











          • @randomSoul I can't get what you mean.

            – Maheer Ali
            56 mins ago












          • See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

            – randomSoul
            51 mins ago












          • @randomSoul See the comments of the answer of certain performance.

            – Maheer Ali
            32 mins ago






          • 2





            @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

            – Yong Quan
            30 mins ago



















          6














          By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you iterate over their Object.keys (which is what the snippet console does). (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)



          See MDN:




          enumerable



          true if and only if this property shows up during enumeration of the properties on the corresponding object.



          Defaults to false.




          Make it enumerable instead:






          //Code Snippet 
          let profile =
          name: 'Barry Allen',


          // I added a new property in the profile object.
          Object.defineProperty(profile, 'age',
          value: 23,
          writable: true,
          enumerable: true
          )

          console.log(profile)
          console.log(profile.age)





          The reason you can see the property in the logged image is that Chrome's console will show you non-enumerable properties as well - but the non-enumerable properties will be slightly greyed-out:



          enter image description here



          See how age is grey-ish, while name is not - this indicates that name is enumerable, and age is not.






          share|improve this answer

























          • Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

            – Maheer Ali
            39 mins ago












          • Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

            – CertainPerformance
            33 mins ago


















          2














          Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.



          //Code Snippet 
          let profile =
          name: 'Barry Allen',


          // I added a new property in the profile object.
          Object.defineProperty(profile, 'age',
          value: 23,
          writable: true,
          enumerable : true,
          configurable : true
          )

          console.log(profile)
          console.log(profile.age)





          share|improve this answer























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            3 Answers
            3






            active

            oldest

            votes








            3 Answers
            3






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            9














            You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.




            enumerable

            true if and only if this property shows up during enumeration of the properties on the corresponding object.
            Defaults to false.




            Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: true
            )
            console.log(profile)
            console.log(profile.age)





            All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.



            To get all properties(including non-enumerable)Object​.get​OwnProperty​Names()
            .






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: false
            )
            for(let key in profile) console.log(key) //only name will be displayed.

            console.log(Object.getOwnPropertyNames(profile)) //You will se age too








            share|improve this answer

























            • I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

              – randomSoul
              1 hour ago











            • @randomSoul I can't get what you mean.

              – Maheer Ali
              56 mins ago












            • See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

              – randomSoul
              51 mins ago












            • @randomSoul See the comments of the answer of certain performance.

              – Maheer Ali
              32 mins ago






            • 2





              @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

              – Yong Quan
              30 mins ago
















            9














            You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.




            enumerable

            true if and only if this property shows up during enumeration of the properties on the corresponding object.
            Defaults to false.




            Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: true
            )
            console.log(profile)
            console.log(profile.age)





            All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.



            To get all properties(including non-enumerable)Object​.get​OwnProperty​Names()
            .






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: false
            )
            for(let key in profile) console.log(key) //only name will be displayed.

            console.log(Object.getOwnPropertyNames(profile)) //You will se age too








            share|improve this answer

























            • I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

              – randomSoul
              1 hour ago











            • @randomSoul I can't get what you mean.

              – Maheer Ali
              56 mins ago












            • See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

              – randomSoul
              51 mins ago












            • @randomSoul See the comments of the answer of certain performance.

              – Maheer Ali
              32 mins ago






            • 2





              @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

              – Yong Quan
              30 mins ago














            9












            9








            9







            You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.




            enumerable

            true if and only if this property shows up during enumeration of the properties on the corresponding object.
            Defaults to false.




            Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: true
            )
            console.log(profile)
            console.log(profile.age)





            All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.



            To get all properties(including non-enumerable)Object​.get​OwnProperty​Names()
            .






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: false
            )
            for(let key in profile) console.log(key) //only name will be displayed.

            console.log(Object.getOwnPropertyNames(profile)) //You will se age too








            share|improve this answer















            You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.




            enumerable

            true if and only if this property shows up during enumeration of the properties on the corresponding object.
            Defaults to false.




            Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: true
            )
            console.log(profile)
            console.log(profile.age)





            All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.



            To get all properties(including non-enumerable)Object​.get​OwnProperty​Names()
            .






            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: false
            )
            for(let key in profile) console.log(key) //only name will be displayed.

            console.log(Object.getOwnPropertyNames(profile)) //You will se age too








            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: true
            )
            console.log(profile)
            console.log(profile.age)





            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: true
            )
            console.log(profile)
            console.log(profile.age)





            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: false
            )
            for(let key in profile) console.log(key) //only name will be displayed.

            console.log(Object.getOwnPropertyNames(profile)) //You will se age too





            let profile = 
            name: 'Barry Allen',


            // I added a new property in the profile object.

            Object.defineProperty(profile , 'age',
            value: 23,
            writable: true,
            enumerable: false
            )
            for(let key in profile) console.log(key) //only name will be displayed.

            console.log(Object.getOwnPropertyNames(profile)) //You will se age too






            share|improve this answer














            share|improve this answer



            share|improve this answer








            edited 28 mins ago

























            answered 1 hour ago









            Maheer AliMaheer Ali

            11.5k826




            11.5k826












            • I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

              – randomSoul
              1 hour ago











            • @randomSoul I can't get what you mean.

              – Maheer Ali
              56 mins ago












            • See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

              – randomSoul
              51 mins ago












            • @randomSoul See the comments of the answer of certain performance.

              – Maheer Ali
              32 mins ago






            • 2





              @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

              – Yong Quan
              30 mins ago


















            • I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

              – randomSoul
              1 hour ago











            • @randomSoul I can't get what you mean.

              – Maheer Ali
              56 mins ago












            • See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

              – randomSoul
              51 mins ago












            • @randomSoul See the comments of the answer of certain performance.

              – Maheer Ali
              32 mins ago






            • 2





              @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

              – Yong Quan
              30 mins ago

















            I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

            – randomSoul
            1 hour ago





            I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying enumerable to false).

            – randomSoul
            1 hour ago













            @randomSoul I can't get what you mean.

            – Maheer Ali
            56 mins ago






            @randomSoul I can't get what you mean.

            – Maheer Ali
            56 mins ago














            See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

            – randomSoul
            51 mins ago






            See - pasteboard.co/IaOxMqB.png . I did not set enumerable to true for age, but still it is shown.

            – randomSoul
            51 mins ago














            @randomSoul See the comments of the answer of certain performance.

            – Maheer Ali
            32 mins ago





            @randomSoul See the comments of the answer of certain performance.

            – Maheer Ali
            32 mins ago




            2




            2





            @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

            – Yong Quan
            30 mins ago






            @randomSoul In Chrome console, you should see unenumerable properties colored a little bit transparent.

            – Yong Quan
            30 mins ago














            6














            By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you iterate over their Object.keys (which is what the snippet console does). (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)



            See MDN:




            enumerable



            true if and only if this property shows up during enumeration of the properties on the corresponding object.



            Defaults to false.




            Make it enumerable instead:






            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable: true
            )

            console.log(profile)
            console.log(profile.age)





            The reason you can see the property in the logged image is that Chrome's console will show you non-enumerable properties as well - but the non-enumerable properties will be slightly greyed-out:



            enter image description here



            See how age is grey-ish, while name is not - this indicates that name is enumerable, and age is not.






            share|improve this answer

























            • Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

              – Maheer Ali
              39 mins ago












            • Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

              – CertainPerformance
              33 mins ago















            6














            By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you iterate over their Object.keys (which is what the snippet console does). (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)



            See MDN:




            enumerable



            true if and only if this property shows up during enumeration of the properties on the corresponding object.



            Defaults to false.




            Make it enumerable instead:






            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable: true
            )

            console.log(profile)
            console.log(profile.age)





            The reason you can see the property in the logged image is that Chrome's console will show you non-enumerable properties as well - but the non-enumerable properties will be slightly greyed-out:



            enter image description here



            See how age is grey-ish, while name is not - this indicates that name is enumerable, and age is not.






            share|improve this answer

























            • Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

              – Maheer Ali
              39 mins ago












            • Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

              – CertainPerformance
              33 mins ago













            6












            6








            6







            By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you iterate over their Object.keys (which is what the snippet console does). (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)



            See MDN:




            enumerable



            true if and only if this property shows up during enumeration of the properties on the corresponding object.



            Defaults to false.




            Make it enumerable instead:






            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable: true
            )

            console.log(profile)
            console.log(profile.age)





            The reason you can see the property in the logged image is that Chrome's console will show you non-enumerable properties as well - but the non-enumerable properties will be slightly greyed-out:



            enter image description here



            See how age is grey-ish, while name is not - this indicates that name is enumerable, and age is not.






            share|improve this answer















            By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you iterate over their Object.keys (which is what the snippet console does). (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)



            See MDN:




            enumerable



            true if and only if this property shows up during enumeration of the properties on the corresponding object.



            Defaults to false.




            Make it enumerable instead:






            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable: true
            )

            console.log(profile)
            console.log(profile.age)





            The reason you can see the property in the logged image is that Chrome's console will show you non-enumerable properties as well - but the non-enumerable properties will be slightly greyed-out:



            enter image description here



            See how age is grey-ish, while name is not - this indicates that name is enumerable, and age is not.






            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable: true
            )

            console.log(profile)
            console.log(profile.age)





            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable: true
            )

            console.log(profile)
            console.log(profile.age)






            share|improve this answer














            share|improve this answer



            share|improve this answer








            edited 34 mins ago

























            answered 1 hour ago









            CertainPerformanceCertainPerformance

            101k166291




            101k166291












            • Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

              – Maheer Ali
              39 mins ago












            • Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

              – CertainPerformance
              33 mins ago

















            • Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

              – Maheer Ali
              39 mins ago












            • Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

              – CertainPerformance
              33 mins ago
















            Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

            – Maheer Ali
            39 mins ago






            Someone give this pasteboard.co/IaOxMqB.png Its showing age property in chrome console. Can you please explain that? Does chrome console works differently?

            – Maheer Ali
            39 mins ago














            Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

            – CertainPerformance
            33 mins ago





            Yes, that's a Chrome console behavior - it'll show you all properties, including non-enumerable ones, see edit. The non-enumerable properties (like age and __proto__) will be slightly greyed out.

            – CertainPerformance
            33 mins ago











            2














            Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.



            //Code Snippet 
            let profile =
            name: 'Barry Allen',


            // I added a new property in the profile object.
            Object.defineProperty(profile, 'age',
            value: 23,
            writable: true,
            enumerable : true,
            configurable : true
            )

            console.log(profile)
            console.log(profile.age)





            share|improve this answer



























              2














              Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.



              //Code Snippet 
              let profile =
              name: 'Barry Allen',


              // I added a new property in the profile object.
              Object.defineProperty(profile, 'age',
              value: 23,
              writable: true,
              enumerable : true,
              configurable : true
              )

              console.log(profile)
              console.log(profile.age)





              share|improve this answer

























                2












                2








                2







                Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.



                //Code Snippet 
                let profile =
                name: 'Barry Allen',


                // I added a new property in the profile object.
                Object.defineProperty(profile, 'age',
                value: 23,
                writable: true,
                enumerable : true,
                configurable : true
                )

                console.log(profile)
                console.log(profile.age)





                share|improve this answer













                Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.



                //Code Snippet 
                let profile =
                name: 'Barry Allen',


                // I added a new property in the profile object.
                Object.defineProperty(profile, 'age',
                value: 23,
                writable: true,
                enumerable : true,
                configurable : true
                )

                console.log(profile)
                console.log(profile.age)






                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered 1 hour ago









                RK_15RK_15

                5899




                5899




















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