How to Convert JSON to Blob in JavaScript ?

This article explores how to convert a JavaScript Object Notation (JSON) object into a Blob object in JavaScript. Blobs represent raw data, similar to files, and can be useful for various tasks like downloading or processing JSON data.

What is JSON and Blob?

• JSON (JavaScript Object Notation): A lightweight format for storing and transmitting data. It uses key-value pairs to represent structured data.
• Blob (Binary Large Object): A Blob represents a raw data object that can hold various types of data, including text, images, or even audio.

Below are the methods for converting JSON data to a Blob object:

Using JSON.stringify and Blob constructor

This approach involves stringifying the JSON object into a human-readable format and then creating a Blob object from the string.

Example: This example shows the use of the above-explained approach.

JavaScript

const {Blob} = require('buffer');
const jsonData = { name: "Example Data", value: 10 };

// Stringify the JSON object
const jsonString = JSON.stringify(jsonData);

// Create a Blob object with the JSON string and 
// set the content type as "application/json"
const blob = 
    new Blob([jsonString], { type: "application/json" });

// Blob object representing the JSON data
console.log(blob); 

Output

Blob { size: 34, type: 'application/json' }

Using fetch API (for pre-existing JSON data)

If you already have the JSON data as a URL, you can use the fetch API to retrieve it and then convert it to a Blob object.

Example: This example shows the use of the above-explained approach.

JavaScript

const jsonUrl = "https://example.com/data.json";

fetch(jsonUrl)
  .then(response => response.blob())
  .then(blob => {
    console.log(blob); // Blob object containing the downloaded JSON data
  })
  .catch(error => console.error(error));
}

Choosing the Right Method:

• Use the first method if you have the JSON data as a JavaScript object.
• Use the second method if you have the JSON data stored remotely as a file accessible through a URL.

Conclusion:

By following these methods, you can effectively convert JSON data into Blobs for further processing or download in your JavaScript applications. Remember to specify the appropriate content type (“application/json”) when creating the Blob to ensure correct data interpretation.