<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<!-- Include the Google CSS package -->
<link rel="stylesheet" href="https://ssl.gstatic.com/docs/script/css/add-ons.css">
<!-- You can also include your own CSS styles -->
<style>
form { margin: 40px auto; }
input { display:inline-block; margin: 20px; }
</style>
<script>
// The function will be called after the form is submitted
function uploadFile() {
document.getElementById('uploadFile').value = "Uploading File..";
google.script.run
.withSuccessHandler(fileUploaded)
.uploadFiles(document.getElementById("labnol"));
return false;
}
// This function will be called after the Google Script has executed
function fileUploaded(status) {
document.getElementById('labnol').style.display = 'none';
document.getElementById('output').innerHTML = status;
}
</script>
<!-- This is the HTML form -->
<form id="labnol">
<!-- Text input fields -->
<input type="text" name="myName" placeholder="Your name..">
<input type="email" name="myEmail" placeholder="Your email..">
<!-- File input filed -->
<input type="file" name="myFile">
<!-- The submit button. It calls the server side function uploadfiles() on click -->
<input type="submit" id="uploadFile" value="Upload File"
onclick="this.value='Uploading..';uploadFile();">
</form>
<!-- Here the results of the form submission will be displayed -->
<div id="output"></div>
