How to create a method in object literal notation?

by

Syntactically, the change is very simple :

var bob = {
  age: 30,
  setAge: function (newAge) {
    bob.age = newAge;
  }
};

But as you can see, there’s a problem : as in your code it uses the external bob variable so this wouldn’t work if you change the value of the bob variable.

You can fix that with 

var bob = {
  age: 30,
  setAge: function (newAge) {
    this.age = newAge;
  }
};

Note that at this point you should check whether what you need isn’t, in fact, a class, which would bring some performance improvements if you have several instances.

Update: ECMAScript 6 now allows methods to be defined the same way regardless of whether they are in an object literal:

var bob = {
  age: 30,
  setAge (newAge) {
    this.age = newAge;
  }
};

More Related Contents:

  1. phone number validation in js [closed]
  2. When is .then(success, fail) considered an antipattern for promises?
  3. What is the JavaScript >>> operator and how do you use it?
  4. Multi-row insert with pg-promise
  5. Dealing with float precision in Javascript [duplicate]
  6. Render basic HTML view?
  7. Memory leak risk in JavaScript closures
  8. Pretty printing XML with javascript
  9. Using querySelectorAll to retrieve direct children
  10. JavaScript double colon (bind operator)
  11. Get function name in JavaScript
  12. What do the different readystates in XMLHttpRequest mean, and how can I use them?
  13. How to auto-scroll to end of div when data is added? [duplicate]
  14. Bootstrap datepicker disabling past dates without current date
  15. jQuery scrolltop firefox not working
  16. What reason is there to use null instead of undefined in JavaScript?
  17. Does Javascript slice method return a shallow copy?
  18. How to play wav audio byte array via javascript/html5?
  19. Most modern method of getting mouse position within a canvas in native JavaScript [duplicate]
  20. Disable elastic scrolling in Safari [duplicate]
  21. Is it good to call subscribe inside subscribe?
  22. JSON schema : “allof” with “additionalProperties”
  23. What is the difference between the $parse, $interpolate and $compile services?
  24. Why is JavaScript prototyping?
  25. Write objects into file with Node.js
  26. Regex for allowing alphanumeric,-,_ and space
  27. How to call parent window function from child window jquery?
  28. round off decimal using javascript
  29. Google maps responsive resize
  30. Getting a sticky header to “push up”, like in Instagram’s iPhone app using CSS and jQuery

Leave a Comment