Node.js querystring.unescape() Method

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The querystring module of node.js provides utilities for parsing and formatting URL query strings. The Node.js querystring.unescape() method decodes the URL percent-encoded characters in the provided string and returns a normal string. This method removes the % symbols from the provided string and returns a normal string.

The Node.js querystring.unescape() method is used by the querystring.parse() method and is not used directly. By default, the querystring.unescape() method tries to use the JavaScript built-in decodeURIComponent() method to decode.

Syntax

Following is the syntax of the Node.js querystring.unescape() method −

querystring.unescape(str)

Parameters

This method accepts four parameters. Those are described below.

• str − This parameter will hold a URL percent−encoded characters which will be decoded into a normal string.

Return Value

This method will decode the given URL percent−encoded characters and returns a normal string.

Example

If we pass a URL percent−encoded characters to Node.js querystring.unescape() method, it will return a Normal string excluding the URL percent−encoded characters.

In the following example, we are encoding a URL percent−encoded string using Node.js querystring.unescape() method.

const querystring = require('node:querystring');

var result = "Articles%20Node.js%20Tutorialspoin";
console.log(querystring.escape(result));

var unescaped = result;
console.log(querystring.unescape(unescaped));

Output

Following is the output of the above code −

internal/modules/cjs/loader.js:596
   throw err;
   ^
   
Error: Cannot find module 'node:querystring'at Function.Module._resolveFilename (internal/modules/cjs/loader.js:594:15)
   at Function.Module._load (internal/modules/cjs/loader.js:520:25)
   at Module.require (internal/modules/cjs/loader.js:650:17)
   at require (internal/modules/cjs/helpers.js:20:18)
   at Object.<anonymous> (/home/cg/root/63a03fcfc3513/main.js:1:83)
   at Module._compile (internal/modules/cjs/loader.js:702:30)
   at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)
   at Module.load (internal/modules/cjs/loader.js:612:32)
   at tryModuleLoad (internal/modules/cjs/loader.js:551:12)
   at Function.Module._load (internal/modules/cjs/loader.js:543:3)

Note − To see actual result, execute the above code in local.

As we can see in the output below, the Node.js querystring.unescape() method returned a normal string.

Articles Node.js Tutorialspoint

Example

The Node.js decodeURIComponent() method will return a Normal string without the URL percent-encoded characters if we pass it a string of URL percent−encoded characters.

The below example demonstrates the usage of the Node.js decodeURIComponent() method.

const querystring = require('node:querystring');
  
let string = "Articles%20Nodejs%20Tutorialspoint";
  
let result = decodeURIComponent(string);

console.log(result)

Output

Following is the output of the above code −

internal/modules/cjs/loader.js:596
   throw err;
   ^
   
Error: Cannot find module 'node:querystring'
   at Function.Module._resolveFilename (internal/modules/cjs/loader.js:594:15)
   at Function.Module._load (internal/modules/cjs/loader.js:520:25)
   at Module.require (internal/modules/cjs/loader.js:650:17)
   at require (internal/modules/cjs/helpers.js:20:18)
   at Object.<anonymous> (/home/cg/root/63a03fcfc3513/main.js:1:83)
   at Module._compile (internal/modules/cjs/loader.js:702:30)at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)
   at Module.load (internal/modules/cjs/loader.js:612:32)
   at tryModuleLoad (internal/modules/cjs/loader.js:551:12)
   at Function.Module._load (internal/modules/cjs/loader.js:543:3)

Note − If we compile and run the above program in local, the Node.js decodeURIComponent() method returns a normal string.

Articles Nodejs Tutorialspoint

Example

If you pass a string including URL percent-encoded characters to both the Node.js querystring.unescape() method and Node.js decodeURIComponent() method, they return the same normal string.

In the following example, we are trying to decode the URL percent-encoded characters by Node.js querystring.unescape() and Node.js decodeURIComponent() methods

const querystring = require('node:querystring');
  
let string = "Articles%20Nodejs%20Tutorialspoint";

let unescaped = querystring.unescape(string)
let decodedURI = decodeURIComponent(string);

console.log("The result of querystring() method: " + unescaped);
console.log("The result of decodeURIComponent() method: " + decodedURI)

if (unescaped === decodedURI){
      console.log("Both the results are same.");
}
else{
      console.log("Both the results are not same");
}

Output

Following is the output of the above code −

internal/modules/cjs/loader.js:596
   throw err;
   ^
   
Error: Cannot find module 'node:querystring'
   at Function.Module._resolveFilename (internal/modules/cjs/loader.js:594:15)
   at Function.Module._load (internal/modules/cjs/loader.js:520:25)
   at Module.require (internal/modules/cjs/loader.js:650:17)
   at require (internal/modules/cjs/helpers.js:20:18)
   at Object.<anonymous> (/home/cg/root/63a03fcfc3513/main.js:1:83)
   at Module._compile (internal/modules/cjs/loader.js:702:30)
   at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)
   at Module.load (internal/modules/cjs/loader.js:612:32)
   at tryModuleLoad (internal/modules/cjs/loader.js:551:12)at Function.Module._load (internal/modules/cjs/loader.js:543:3)

Note − To see actual result, execute the above code in local.

After executing the above program, both the methods returned the same string.

The result of querystring() method: Articles Nodejs Tutorialspoint
the result of decodeURIComponent() method: Articles Nodejs Tutorialspoint
Both the results are same.