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kheersagar parja
kheersagar parja

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Asynchronous to Synchronous JavaScript

#webdev #javascript #programming #interview

Popular JavaScript Interview Question

How to Convert Asynchronous code to Synchronous code ?
Promises can be used to convert Asynchronous code to Synchronous code.

Example
Asynchronous setTimeout Function

console.log("Before setTimeout") setTimeout(()=>{ console.log("Inside setTimeout") },1000) console.log("After setTimeout")
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Output 

Before setTimeout After setTimeout Inside setTimeout
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Convert Asynchronous setTimeout Function to Synchronous

console.log("Before setTimeout") //await will wait for JS to resolve the promise await new Promise((resolve,reject)=>{ setTimeout(()=>{ //after 1000ms promise will be resolved resolve(console.log("Inside setTimeout")) },1000) }) console.log("After setTimeout")
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Output 

Before setTimeout Inside setTimeout After setTimeout
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