Skipping optional function parameters in JavaScript

by

Solution:

goog.net.XhrIo.send(url, undefined, undefined, undefined, {'Cache-Control': 'no-cache'})

You should use undefined instead of optional parameter you want to skip, because this 100% simulates the default value for optional parameters in JavaScript.

Small example:

myfunc(param);

//is equivalent to

myfunc(param, undefined, undefined, undefined);

Strong recommendation: use JSON if you have a lot of parameters, and you can have optional parameters in the middle of the parameters list. Look how this is done in jQuery.

More Related Contents:

  1. How to get function parameter names/values dynamically?
  2. How can I remove a specific item from an array?
  3. How do I check if an element is hidden in jQuery?
  4. JavaScript inheritance and the constructor property
  5. jQuery object and DOM element
  6. How do you clone an array of objects in JavaScript?
  7. React Native: require() with Dynamic String?
  8. Pass arguments with page.evaluate
  9. How to keep an Javascript object/array ordered while also maintaining key lookups?
  10. How does setInterval and setTimeout work?
  11. JavaScript listener, “keypress” doesn’t detect backspace?
  12. Remembering state before app goes in foreground
  13. Why JavaScript functions always return a value?
  14. Defer Attribute (Chrome)
  15. jQuery.getScript alternative in native JavaScript
  16. How to stop an animated gif from looping
  17. Fetch image from API
  18. Is there a ‘has focus’ in JavaScript (or jQuery)?
  19. How to detect when history.pushState and history.replaceState are used? [duplicate]
  20. ReactJs: Prevent multiple times button press
  21. Animating Multiple Markers
  22. Nodejs: how to clone an object
  23. How to get an element by its href in jquery?
  24. How to negate code in “if” statement block in JavaScript -JQuery like ‘if not then..’
  25. Android Phonegap – How to Open Native Google Maps Application
  26. Can a JavaScript variable be used in plain HTML?
  27. How to Inject Angular2 Http service into es6/7 Class?
  28. How to use npm modules in browser? is possible to use them even in local (PC)?
  29. Why is iframe.contentWindow == null?
  30. Looping through Markers with Google Maps API v3 Problem

Leave a Comment