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JS AJAX to post generated file as PDF to server directory

I have a complex table generated via javascript that I'd like to save as PDF on the server. I've looked around at the pdf generation libraries and they all seem to be limited in terms of style, fonts, etc (that's what I meant by 'complex'). The table can be download client side as PDF or printed.
Let's say my function that generates the form to be printed is reportBody(data); - is there a way I can use AJAX to send the document as PDF to a php file that will save it server-side instead of downloading it client-side? The reportBody(data) is a collection of other variables, function calls etc.
So basically the question is - since we can generate a PDF file client-side, can we POST it (the pdf) via ajax to the server?

Short answer is Yes. Your provided information is still limited as it's not clear what is ran in the reporBody(data) but most PDF libraries on client side are able to give you the PDF file as base64 encoded data in form of a string.
You can then simply send that string to the server and save that as a PDF file.
A simple implementation will be something like this:
// I have used jQuery for convenience but you can use any lib or Vanilla JS
var saveData = $.ajax({
type: 'POST',
url: "url-to-the-php-script",
data: { pdfData: 'base64StringDataHere'},
dataType: "JSON",
success: function(resultData) { alert("Save Complete") }
});
Then on server side, do something like this:
$pdfData= $_POST['pdfData'];
file_put_contents('filename.pdf', base64_decode($pdfData));

Yes, there are a lot of ways. One would be, if you have html code in your reportBody(data); you could:
Send the html to a php file via ajax
in this php you could use https://wkhtmltopdf.org/ to generate a pdf file
In the client side you could point to that pdf generated

External URL linking

I have the following code:
<script>
var fileContent;
$.ajax({
url : "text.txt",
dataType: "text",
...
It loads the text from a .txt file in order to obtain the data. If the text.txt is on the same path as the html code, it loads the data. However, if I type for example (placing the file in a different folder):
url: "../../../files/text.txt"
It does not allow me to obtain the file. Any ideas of how to do it or how to implement it without changing the code in a significant way? Thanks!

There are three possible causes of this:
You are using HTTP
You are using HTTP and the path you are trying to access is not exposed by your web server. (You cannot access files above the directory root by default).
You need to give the file a URL on your web server and request that URL.
You are using local files
Different browsers have different security restrictions for Ajax on local files.
You can get this problem if the file is in a directory above the HTML document (some browsers only allow you to access files in the same or a lower directory).
You can resolve this by using HTTP. Ajax in general works very poorly without HTTP.
You simply have the URL wrong
Correct the URL.

Easiest way to load and read a local text file with javascript?

I have a .csv file that I wish to load that contains information that the .HTML page will format itself with. I'm not sure how to do this however,
Here's a simple image of the files: http://i.imgur.com/GHfrgff.png
I have looked into HTML5's FileReader and it seems like it will get the job done but it seems to require usage of input forms. I just want to load the file and be able to access the text inside and manipulate it as I see fit.
This post mentions AJAX, however the thing is that this webpage will only ever be deployed locally, so it's a bit iffy.
How is this usually done?

Since your web page and data file are in the same directory you can use AJAX to read the data file. However I note from the icons in your image that you are using Chrome. By default Chrome prevents just that feature and reports an access violation. To allow the data file to be read you must have invoked Chrome with a command line option --allow-file-access-from-files.
An alternative, which may work for you, is to use drag the file and drop into onto your web page. Refer to your preferred DOM reference for "drag and drop files".

You can totally make an ajax request to a local file, and get its content back.
If you are using jQuery, take a look at the $.get() function that will return the content of your file in a variable. You just to pass the path of your file in parameter, as you would do for querying a "normal" URL.

You cannot make cross domain ajax requests for security purposes. That's the whole point of having apis. However you can make an api out of the $.get request URL.
The solution is to use YQL (Yahoo Query Language) which is a pretty nifty tool for making api calls out of virtually any website. So then you can easily read the contents of the file and use it.
You might want to look at the official documentation and the YQL Console
I also wrote a blog post specifially for using YQL for cross domain ajax requests. Hope it helps

You can try AJAX (if you do not need asynchronous processing set "async" to false. This version below ran in any browser I tried when employed via a local web server (the address contains "localhost") and the text file was indeed in the UTF-8-format. If you want to start the page via the file system (the address starts with "file"), then Chrome (and likely Safari, too, but not Firefox) generates the "Origin null is not allowed by Access-Control-Allow-Origin."-error mentioned above. See the discussion here.
$.ajax({
async: false,
type: "GET",
url: "./testcsv.csv",
dataType: "text",
contentType: "application/x-www-form-urlencoded;charset=UTF-8",
success: function (data) {
//parse the file content here
}
});
The idea to use script-files which contain the settings as variables mentioned by Phrogz might be a viable option in your scenario, though. I was using files in the "Ini"-format to be changed by users.

Why threre is no way to download file using ajax request?

In our application we need to implement following scenario:
A request is send from client
Server handles the request and generates file
Server returns file in response
Client browser displays file download popup dialog and allows user to download the file
Our application is ajax based application, so it would be very easy and convenient for us to send ajax request (like using jquery.ajax() function).
But after googilng, it turned out that file downloading is possible only when using non-ajax POST request (like described in this popular SO thread). So we needed to implement uglier and more complex solution that required building HTML structure of form with nested hidden fields.
Could someone explain in simple words why is that ajax requests cannot be used to download file? What's the mechanics behind that?

It's not about AJAX. You can download a file with AJAX, of course. However the file will be kept in memory, i.e. you cannot save file to disk. This is because JavaScript cannot interact with disk. That would be a serious security issue and it is blocked in all major browsers.

This can be done using the new HTML5 feature called Blob. There is a library FileSaver.js that can be utilized as a wrapper on top of that feature.

That's the same question I'd asked myself two days ago. There was a project with client written using ExtJS and server side realisation was on ASP.Net. I have to translate server side to Java. There was a function to download an XML file, that server generates after Ajax request from the client. We all know, that it's impossible to download file after Ajax request, just to store it in memory. But ... in the original application browser shows usual dialog with options open, save and cancel downloading. ASP.Net somehow changed the standard behaviour... It takes me two day to to prove again - there is no way to download file by request usual way ... the only exception is ASP.Net... Here is ASP.Net code
public static void WriteFileToResponse(byte[] fileData, string fileName)
{
var response = HttpContext.Current.Response;
var returnFilename = Path.GetFileName(fileName);
var headerValue = String.Format("attachment; filename={0}",
HttpUtility.UrlPathEncode(
String.IsNullOrEmpty(returnFilename)
? "attachment" : returnFilename));
response.AddHeader("content-disposition", headerValue);
response.ContentType = "application/octet-stream";
response.AddHeader("Pragma", "public");
var utf8 = Encoding.UTF8;
response.Charset = utf8.HeaderName;
response.ContentEncoding = utf8;
response.Flush();
response.BinaryWrite(fileData);
response.Flush();
response.Close();
}
This method was called from WebMethod, that, in turn, was called from ExtJS.Ajax.request. That's the magic. What's to me, I've ended with servlet and hidden iframe...

you can do this by using hidden iframe in your download page
just set the src of the hidden ifame in your ajax success responce and your task is done...
$.ajax({
type: 'GET',
url: './page.php',
data: $("#myform").serialize(),
success: function (data) {
$("#middle").attr('src','url');
},
});

Reading local XML file with javascript

I am new to HTML/Javascript, as well as coding in general so bear with me :). I am trying to create a "Spot the Difference" game in html5 using javascript. Everything is local (on my machine). I have two pictures, of the same size, one with differences. To generate data about the clickable fields, I have a java program that reads both of the images and outputs all of the positions in which pixels are different into a XML file. My plan was to then use this XML file with my javascript to define where the user could click. However, it appears (correct me if I'm wrong) that javascript cannot read local XML files for security reasons. I do not want to use an ActiveXObject because I plan on putting this onto mobile devices via phone gap or a webkit object. Does anyone have a better approach to this problem, or perhaps a way to read local XML files via javascript? Any help would be greatly appreciated, thanks.

If you are planning to put this into a smart phones (iOS and Android) and read local files, I have done similar things with JSON (yes, please don't use XML).
Convert your output to JSON
Put this as part of your application package. For example, in Android, I put it as part of the .apk in /appFiles/json
Create a custom content provider that would read the local file. I create mine as content:// but you create whatever scheme you want. You could leverage android.content.ContentProvider in order to achieve custom URL Scheme. iOS has its own way to create custom scheme as well. The implementation simply read your local storage and give the content
To read it from Javascript, I simply call ajax with the custom scheme to get the json file. For example content://myfile/theFile.json simply redirect me to particular directory in local storage with /myfile/theFile.json appended to it
Below is the sample to override openFile() in the ContentProvider
public ParcelFileDescriptor openFile (Uri uri, String mode) {
try {
Context c = getContext();
File cacheDir = c.getCacheDir();
String uriString = uri.toString();
String htmlFile = uriString.replaceAll(CUSTOM_CONTENT_URI, "");
// Translate the uri into pointer in the cache
File htmlResource = new File(cacheDir.toString() + File.separator + htmlFile);
File parentDir = htmlResource.getParentFile();
if(!parentDir.exists()) {
parentDir.mkdirs();
}
// get the file from one of the resources within the local storage
InputStream in = WebViewContentProvider.class.getResourceAsStream(htmlFile);
// copy the local storage to a cache file
copy(in, new FileOutputStream(htmlResource));
return ParcelFileDescriptor.open(htmlResource, ParcelFileDescriptor.MODE_READ_WRITE);
} catch(Exception e) {
throw new RuntimeException(e);
}
}
I hope it helps

I would suggest modifying your java program to output a JSON formatted file instead of XML. JSON is native to JavaScript and will be much simpler for you to load.
As for actually loading the data, i'm not sure what the best option is as you say you want to evenutally run this on a mobile device. If you were just making a normal website you could setup a web server using either Apache or IIS depending on your OS and put the files in the document root. Once you've done that you can load the JSON file via Ajax, which can easily be googled for.
Not sure if this helps any.

Since this is a local file, you can do this with jQuery
$.ajax({
type: "GET",
url: "your.xml",
dataType: "xml",
success: function(xml){
///do your thing
}
});
http://api.jquery.com/jQuery.ajax/