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JavaScript Asynchronous Programming with JavaScript What is Asynchronous Programming? Examples of Synchronous and Asynchronous Code

Posted by Moritz Wallawitsch
Moritz Wallawitsch
736 Points

Help: I didn't saw a change made to the asynchronous code in the second example. Additionally I cant unzip the workfile

... Because there is one file with a question mark in it. But that's only a minor problem.

Elisa Burghard
Elisa Burghard
9,276 Points
Elisa Burghard
Elisa Burghard
9,276 Points

changes I saw:

  • line 3(synchronous) to line 4(asynchronous) xhr.open('GET', url) // omitted 'false'
  • line 10(synchronous) to line 11(asynchronous) xhr.send() // omitted 'null'

Hope this helps and happy coding!

1 Answer

jlampstack
jlampstack
23,932 Points
jlampstack
jlampstack
23,932 Points

Hi, The 3rd arg in the open() method was updated from false to true. Originally it was set as false. Guil simply removed the 3rd arg since it's optional. If the 3rd arg isn't explicitly set JavaScript uses true as its default value. You can explicitly set it to true if you'd like but it's not necessary.

open(method, url, async)

More Info https://www.w3schools.com/js/js_ajax_http_send.asp