Validating JSON Strings in JavaScript

Introduction

In this lab, we will be exploring how to check if a provided string is valid JSON using JavaScript. We will be using the JSON.parse() method along with a try...catch block to determine the validity of the provided string. This lab will help you to better understand how to work with JSON data in JavaScript.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL javascript(("`JavaScript`")) -.-> javascript/BasicConceptsGroup(["`Basic Concepts`"]) javascript(("`JavaScript`")) -.-> javascript/AdvancedConceptsGroup(["`Advanced Concepts`"]) javascript(("`JavaScript`")) -.-> javascript/NetworkingGroup(["`Networking`"]) javascript/BasicConceptsGroup -.-> javascript/variables("`Variables`") javascript/BasicConceptsGroup -.-> javascript/data_types("`Data Types`") javascript/BasicConceptsGroup -.-> javascript/arith_ops("`Arithmetic Operators`") javascript/BasicConceptsGroup -.-> javascript/comp_ops("`Comparison Operators`") javascript/AdvancedConceptsGroup -.-> javascript/error_handle("`Error Handling`") javascript/AdvancedConceptsGroup -.-> javascript/destr_assign("`Destructuring Assignment`") javascript/NetworkingGroup -.-> javascript/json("`JSON`") subgraph Lab Skills javascript/variables -.-> lab-28449{{"`String Is Valid JSON`"}} javascript/data_types -.-> lab-28449{{"`String Is Valid JSON`"}} javascript/arith_ops -.-> lab-28449{{"`String Is Valid JSON`"}} javascript/comp_ops -.-> lab-28449{{"`String Is Valid JSON`"}} javascript/error_handle -.-> lab-28449{{"`String Is Valid JSON`"}} javascript/destr_assign -.-> lab-28449{{"`String Is Valid JSON`"}} javascript/json -.-> lab-28449{{"`String Is Valid JSON`"}} end

Check If A String Is Valid JSON

To check if a given string is valid JSON, follow these steps:

Open the Terminal/SSH and type node to start practicing coding.
Use the JSON.parse() method and a try...catch block to check if the provided string is valid JSON.
If the string is valid, return true. Otherwise, return false.

Here's an example code snippet that implements this logic:

const isValidJSON = (str) => {
  try {
    JSON.parse(str);
    return true;
  } catch (e) {
    return false;
  }
};

You can test this function with different input strings, like this:

isValidJSON('{"name":"Adam","age":20}'); // true
isValidJSON('{"name":"Adam",age:"20"}'); // false
isValidJSON(null); // false

In the last example, null is not a valid JSON string, so the function returns false.

Summary

Congratulations! You have completed the String Is Valid JSON lab. You can practice more labs in LabEx to improve your skills.

String Is Valid JSON

Introduction

Skills Graph

Check If A String Is Valid JSON

Summary

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