Upload an image converted to `toDataURL` to the server

I've been attempting to integrate the signature_pad library, found at signature_pad, but I am struggling to grasp its functionality.

Can someone guide me on how to retrieve an image value and send it to my server?

Edit:

I have experimented with decoding:

In JavaScript "app.js":

saveButton.addEventListener("click", function (event) {
    if (signaturePad.isEmpty()) {
        alert("Please provide signature first.");
    } else {
        saveSignature(signaturePad.toDataURL());
    }
});

function saveSignature(dataURL) {
$.ajax({
  type: "POST",
  url: "script.php",
  data: { 
     imgBase64: dataURL
  }
}).done(function(o) {
  console.log('saved'); 
});
}

In PHP, "script.php":

<?php
    // requires php5
    define('UPLOAD_DIR', 'images/');
    $img = $_POST['img'];
    $img = str_replace('data:image/png;base64,', '', $img);
    $img = str_replace(' ', '+', $img);
    $data = base64_decode($img);
    $file = UPLOAD_DIR . uniqid() . '.png';
    $success = file_put_contents($file, $data);
    print $success ? $file : 'Unable to save the file.';
?>

Answer №1

Ensure to retrieve $_POST['imgBase64'] in your PHP code instead of using $_POST['img'].

Your PHP script is not outputting data in json format.

Consider updating your code like this:

echo json_encode(['result' => $success ? $file : 'Unable to save the file.'])

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