JavaScript | Callbacks

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JavaScript callbacks can be used to process the result of async operation. Lets take a example below.

As shown in below example the callback function is used to process the response received from rest service.

See the Pen by Rohan (@rohanlopes20) on CodePen.


Things gets complicated when we have to call more than one request on after another like second request is depending upon response of first request. This leads to callback hell. I recommend to read more on https://javascript.info/callbacks

As you chain more and more calls it becomes complicated to maintained code. This can be avoided with JavaScript Promises.

See the Pen by Rohan (@rohanlopes20) on CodePen.

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