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Hi Team

I am struggling if it will be possible to save a signature as a file format to the db record, i need some help the only example i seen so far are store it locally.

What I have tried:

// HTML code
<div class="wrapper">
  <canvas id="signature-pad" class="signature-pad" width=400 height=200></canvas>

<button id="save-png">Save as PNG</button>
<button id="save-jpeg">Save as JPEG</button>
<button id="save-svg">Save as SVG</button>
<button id="draw">Draw</button>
<button id="erase">Erase</button>
<button id="clear">Clear</button>

// javascript
var canvas = document.getElementById('signature-pad');

// Adjust canvas coordinate space taking into account pixel ratio,
// to make it look crisp on mobile devices.
// This also causes canvas to be cleared.
function resizeCanvas() {
    // When zoomed out to less than 100%, for some very strange reason,
    // some browsers report devicePixelRatio as less than 1
    // and only part of the canvas is cleared then.
    var ratio =  Math.max(window.devicePixelRatio || 1, 1);
    canvas.width = canvas.offsetWidth * ratio;
    canvas.height = canvas.offsetHeight * ratio;
    canvas.getContext("2d").scale(ratio, ratio);

window.onresize = resizeCanvas;

var signaturePad = new SignaturePad(canvas, {
  backgroundColor: 'rgb(255, 255, 255)' // necessary for saving image as JPEG; can be removed is only saving as PNG or SVG

document.getElementById('save-png').addEventListener('click', function () {
  if (signaturePad.isEmpty()) {
    return alert("Please provide a signature first.");
  var data = signaturePad.toDataURL('image/png');

document.getElementById('save-jpeg').addEventListener('click', function () {
  if (signaturePad.isEmpty()) {
    return alert("Please provide a signature first.");

  var data = signaturePad.toDataURL('image/jpeg');

document.getElementById('save-svg').addEventListener('click', function () {
  if (signaturePad.isEmpty()) {
    return alert("Please provide a signature first.");

  var data = signaturePad.toDataURL('image/svg+xml');

document.getElementById('clear').addEventListener('click', function () {

document.getElementById('draw').addEventListener('click', function () {
  var ctx = canvas.getContext('2d');
  ctx.globalCompositeOperation = 'source-over'; // default value

document.getElementById('erase').addEventListener('click', function () {
  var ctx = canvas.getContext('2d');
  ctx.globalCompositeOperation = 'destination-out';
Richard MacCutchan 8-Mar-23 3:25am    
You can save any information to a database. You can save the file contents as a BLOB type, or save the file on normal storage. and save its location to the database. Which you choose is up to you.
Gcobani Mkontwana 8-Mar-23 3:59am    
@Richard McCutchan given the javascript, how can i do that with this code..? any example perhaps

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