Question

How to use function in JSON.parse with JavaScript

Answer 1

const json = '{"1": "A", "2": "B", "3": "C", "4": "D", "5": "E"}';

const parsedJson = JSON.parse(json, (key, value) => {
    if (key == 3)
        console.log('key == 3');

    if (key == 5)
		console.log('key == 5');

    return value; 
});

console.log(parsedJson);



  
/*
run:

key == 3
key == 5
{ '1': 'A', '2': 'B', '3': 'C', '4': 'D', '5': 'E' }

*/

 

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Answer 2

const json = '{"1": "A", "2": "B", "3": "C", "4": "D", "5": "E"}';
 
const parsedJson = JSON.parse(json, (key, value) => {
	console.log(key, value);
});
 
 
 
   
/*
run:
 
1 A
2 B
3 C
4 D
5 E
 {}
 
*/

 

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Answer 3

const json = '{"1": "A", "2": "B", "3": "C", "4": "D", "5": "E"}';
 
const parsedJson = JSON.parse(json, (key, value) => {
    if (key == 3)
        return 'JavaScript';
 
    if (key == 5)
		return 'Node.js';
 
    return value; 
});
 
console.log(parsedJson);
 
 
 
   
/*
run:
 
{ '1': 'A', '2': 'B', '3': 'JavaScript', '4': 'D', '5': 'Node.js' }
 
*/

 

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