File Upload

Thanks, still a little confused by the example. How would I go about saving the actual file? My use case is allowing the end user to upload vendor documentation (could be Word documents, PowerPoint, etc) that is then cataloged in specific directories on the server and linked to in other code on the website. It appears that I need to do something in the file: options.files[0] line but I am missing something. Do you have further documentation? I used the plnkr example and put it on my own server. I changed the content line to match the location on my server where I want to the file to be saved, but nothing appears there.
I appreciate your help.

Hello

I'll try to clarify the events usage;

JavaScript
survey.onUploadFiles.add(function(sender, options) {
    // Here you need to iterate through the options.files array and post each file content to your server
    // Server should return some unique id string (an id or an url) identifying the file
    // ....
    // After all files posted you need to call options.callback function and pass 
    // an array of objects containig corresponding file has been sent and unique id string has been returned for the file
      options.callback("success", [
        {
          file: options.files[0], // file has been sent
          content: // the unique id string has been returned for the file
                        // in this case this is a simple URL
                        // it can be a GUID or some unique string
            "https://surveyjs.io/Content/Images/examples/image-picker/panda.jpg"
        }
      ]);
  });

JavaScript
survey.onDownloadFile.add(function(sender, options) {
 // options.content - is the unique id string has been returned for the file
 // you can get the file from your server by this id
 // from server you can obtain a link or a base64 encoded file content
   options.callback(
     "success",
     "https://surveyjs.io/Content/Images/examples/image-picker/panda.jpg" // here nav be any valid value for the SRC attribute of the IMAGE tag (for preview) - a link or a base64 encoded file content
   );
});

Hope it will help

Thanks, Serge
SurveyJS Team

So I guess the part I am missing is in your comments to iterate thorugh the array and post the content. Am I supposed to use a survey.js function (uploadFiles) or some sort of generic Javascript commands? I found that when I change the storeDataAsText to true, the output of the result.data gives me the name of the file, the datatype, and the actual base64 code of the file (for example see below)
result: {"file":[{"name":"collection manager notes.txt","type":"text/plain","content":"data:text/plain;base64,L2V0Yy9pbml0dGFiIG50cGRhdGUgMTAuMC42LjU4DQovZXRjL250cC5jb25mIDEwLjAuNi41OA0Kb24gMTAuMjAwLjYwLjcxLTczIChsY…"}]}
I tried doing an AJAX call to a PHP file to handle the data and perhaps create a file using the base64 data as the content of the file, but my variables ending up being blank (I am guessing that maybe the amount of data being sent across to PHP is too large.

var surveydata = (result.data);
$.post("doctest.php",{data: surveydata});

<?php
$fileinfo = $_POST['data'];
filename = $fileinfo["file"]["name"];
filetype = $fileinfo["file"]["type"];
filecontent = $fileinfo["file"]["content"];
?>
I apologize for my ineptitude here, but it just isn't clicking for me.

We haven't a sample how to work with files in PHP. I beleive it can be googled.

We have a sample repo with PHP backend https://github.com/surveyjs/surveyjs-php/
You can check this client-side https://github.com/surveyjs/surveyjs-php/blob/master/editor.js
And this PHP file https://github.com/surveyjs/surveyjs-php/blob/master/index.php
As example how to process POST requests

Thanks, Serge
SurveyJS Team

Okay, so I have been able to build out a way to do this.
In my .js file I post the entire survey results (as I had already been doing to work with the other data).
survey
.onComplete
.add(function (result) {
var surveydata = result.data;
$.post("doctest.php",{data: surveydata});
});

In my PHP file, I grab the contents of the file upload question and save to the local server

$fileinfo = $_POST['data'];
$file = $fileinfo["file"];
$filename = $file[0]["name"];
$filedata = $file[0]["content"];
$filedata = preg_replace('#data:.*\bbase64\b,#','',$filedata); \Remove the file type data from the Base64 encoded data of the actual file
$filepath = "/var/www/request/docs/".$filename;
$data = base64_decode($filedata);
file_put_contents($filepath,$data);

This works so far with smaller files (less than 1MB), but I have had some problems with larger ones. In my research on file_put_contents it looks like there are some methods for buffering the data in order to handle larger files. Also, in the full spectrum of my survey I am using a dynamic panel for the file upload question so I will have to make use of a loop to go through each file, but it looks like I have the basic idea down now for being able to write the files. Thanks for your help.

After some more testing, it looks like when adding a larger file there is a pause when hitting the Submit button and display the results.data on the page and the details from the file are not complete. Is there a size limit on how large the results.data can be?

I found some html/php scripts that allow larger files to be uploaded and very quickly. I am trying to use the logic behind these scripts to enter my code into the onUploadFiles function. Basically it works by peforming a POST function from a HTML form using enctype multipart/form-data and the $_FILES environment variable in PHP. I am looking at figuring out a way to send the same information from the OnUploadFiles function to my PHP. Could you tell me the structure of the options.files array? In doing some testing, I have found the following two values:
options.files[x]["name"]
options.files[x]["type"]

What are the other values in this array?
Thanks.