save html5 canvas output to my rails app

Question

I am trying to save the content of a html5 canvas to my Rails app. I found the

var url = canvas.toDataURL(\'image/png\');

but I cant figur

Answer 1

simply place the content of url in an hidden field.

in javascript (with jquery):

var url = canvas.toDataURL('image/png');
$("#canvascontent").val(url);