How Can I Convert an Image to a Base64 String in JavaScript?

Convert an Image to Base64 String in JavaScript

Converting an image to a Base64 string is a common task in web development, especially when you need to send an image to a server. Here are two popular JavaScript approaches to achieve this:

1. FileReader Approach:

This approach utilizes the FileReader API to read the image as a blob and then convert it to a data URL:

function toDataURL(url, callback) {
  var xhr = new XMLHttpRequest();
  xhr.onload = function() {
    var reader = new FileReader();
    reader.onloadend = function() {
      callback(reader.result);
    }
    reader.readAsDataURL(xhr.response);
  };
  xhr.open('GET', url);
  xhr.responseType = 'blob';
  xhr.send();
}

toDataURL('https://www.gravatar.com/avatar/d50c83cc0c6523b4d3f6085295c953e0', function(dataUrl) {
  console.log('RESULT:', dataUrl)
})

2. HTML Canvas Approach:

Another option is to create an HTML canvas, draw the image onto it, and then convert the canvas to a data URL:

const canvas = document.createElement('canvas');
const ctx = canvas.getContext('2d');

// Resize the canvas to the image's size
canvas.width = image.width;
canvas.height = image.height;

// Draw the image onto the canvas
ctx.drawImage(image, 0, 0);

// Convert the canvas to a data URL
const dataUrl = canvas.toDataURL('image/jpeg');

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