how can i check with php, if in field was a signed

[speedloc]

hi all, i need a option in php to check, if in signature_apd field was a signed or it was not clean. any ideas? regards

[UziTech]

PHP is a server side language, signature_pad is a client side library, how are you sending the data from signature_pad to the server?

[ZenithElevate]

I hope @UziTech does not mind me giving the OP a hand.
On the PHP side, you will have to use isset() on the $_POST[] item. You get the value for that item, from the client side, by assigning the signature to a hidden input, during the form submit. To know that your signature pad is signed, in your JS, you use the API:

if(signaturePad.isEmpty()) {
  alert('Must sign');
} else {
  input_id.value = signaturePad.toDataUrl('image/png');
}

or something along these lines.

[speedloc]

hi isset($_POST[]) dont work, well it was evertytime set but not filled. js i know but i need it to check in php ;(
i send it with hidden field and post in php but if it was clean it was set already and emty dont work too. i dont have foudn a way to check it in php :( hope any have a idea or a workaround

[ZenithElevate]

We've literally just gone over the same questions, with @UziTech, a few days back. Check out our earlier questions. The code above is literally from our now-working solution that he helped to devise. So yes, it works both in JS and PHP.

Did you ensure that your code is assigning the sig to the hidden, in your onsubmit?

[speedloc]

hi, yes it comes with base64 in hoidden field, but hidden field is set every time, isset show also every time yes, but if it was blank isset show yes to well vlaue is set ever.

code: <div id="signature-pad" class="m-signature-pad"> <div class="m-signature-pad--body"> <canvas></canvas> <input type="hidden" name="signature" id="signature" value=""> </div> </div> <div align="right"><a href="#signature" onclick="signaturePad.clear();">Unterschrift zur&uuml;cksetzen!</a></div>

after check with
if(isset($_POST['signature'])) echo "is set"; else echo "is not set" every is come is set. well varaible is set every time with blank or filled. they is also not a option to check it.

[UziTech]

Can you check before setting the hidden input and only set the hidden input of it is there?

[speedloc]

how you mean? if i dont have a hidden field or before it comes, i cant check it wll what do i use for test?

[UziTech]

Check for isEmpty before setting the hidden field.

// js
function onSubmit() {
  if (signaturePad.isEmpty()) {
    myHiddenField.value = '';
  } else {
    myHiddenField.value = signaturePad.toDataUrl();
  }
}

// php
if (isset($_POST['myHiddenField')) {
  // its not empty
} else {
  // its empty
}

[speedloc]

hi, thanks js if was solution here... well ihave set everytime myHiddenField.value = signaturePad.toDataUrl(); with if it works fine.
thanks^^ and best regards