I use jquery jtable send ajax to get excel file from server but Response::download doesn't work
$writer = (new WriterFactory())->createWriter(new Excel5(public_path().'/file/myExport.xls'));
$phpExcel = $writer->convert($workbook);
$writer->write($phpExcel);
Response::download(public_path().'\file\myExport.xls');
Javascript cannot access file system, you cannot use ajax to download files. Try using an iframe pointing to the file to download it.
<iframe id="downloadFrame" style="display:none"/>
When you need to download, use this script:
var iframe = document.getElementById("downloadFrame");
iframe.src = "yourpathtofile";
If you use jQuery, you can try:
$("#downloadFrame").attr("src","yourpathtofile");
Another solution is using window.open
window.open("pathtoyourfle");
Related
I have uploaded an image on a server powered by Golang. I want to show the same image in a HTML / JS page using XMLHttpRequest (XHR).
I'm having following challenges -
The static file server
http.Handle("/public/", http.StripPrefix("/public/", http.FileServer(http.Dir("public"))))
is local to Go system and its template system. The Javascript doesn't know this system and can't find the required file.
So, while the img in HTML works (img src="/public/300x300.gif") works, this -
xhr.open("GET", "/public/300x300.gif", true);
xhr.overrideMimeType('text/plain; charset=x-user-defined');
xhr.send();
is not working.
How can I load an image on the page using AJAX while the file is available in Golang's virtual file system?
Can I send a file as multipart by XMLHttpRequest to a servlet?
I am making a form and submitting it as multipart, but somehow I am not getting a response for successfully uploading it. I do not want the page to be refreshed, so it has to take place by Ajax.
That's only possible with the XHR FormData API (previously known being part of as "XHR2" or "XHR Level 2", currently known as "XHR Advanced Features").
Given this HTML,
<input type="file" id="myFileField" name="myFile" />
you can upload it as below:
var formData = new FormData();
formData.append("myFile", document.getElementById("myFileField").files[0]);
var xhr = new XMLHttpRequest();
xhr.open("POST", "myServletUrl");
xhr.send(formData);
XHR will take care about proper headers and request body encoding and the file will in this example be available on the server side as form-data part with the name myFile.
You need to keep in mind that FormData API is not supported in older browsers. At caniuse.com you can see that it's currently implemented in Chrome 7+, Firefox 3.5+, Safari 5+, Internet Explorer 10+ and Opera 12+.
In case you're using jQuery, then you might be tempted to use its $.val() function as below:
formData.append("myFile", $("#myFileField").val());
But this is incorrect as it doesn't return the whole File object, but merely the file name as String which is utterly useless as it doesn't contain the file contents.
If you don't want to use document.getElementById() for some reason, then use one of the following instead:
formData.append("myFile", $("#myFileField").prop("files")[0]);
formData.append("myFile", $("#myFileField")[0].files[0]);
An alternative is to use the jQuery Form plugin. Your entire form, when written and functioning properly without any line of JavaScript code, will then instantly be ajaxified with just the following line:
$("#formId").ajaxForm(function(response) {
// Handle Ajax response here.
});
It also supports file uploads as well by a hidden iframe trick. See also this jQuery Form documentation for an in-depth explanation. You may only need to change the servlet code to be able to intercept on both normal (synchronous) and Ajax (asynchronous) requests. See also this answer for a concrete example: Simple calculator with JSP/Servlet and Ajax
Either way, the uploaded file should then be available in the doPost() method of a #MultipartConfig servlet as follows:
Part myFile = request.getPart("myFile");
Or if you're still on Servlet 2.5 or older, use Apache Commons FileUpload the usual way. See also this answer for a concrete example: How can I upload files to a server using JSP/Servlet?
It's not possible to send multipart/form-data with XMLHttpRequest (though it is possible in modern browsers, with XHR2. See BalusC's answer).
A common way to achieve what you want is to use a regular form, but in an iframe instead. This way, only the iframe is refreshed on upload.
I wanna know how to read text file from django server using ajax? or something else.
I searched about using XMLHttpRequest and It worked when I tryed to get django template html file. but I couldn't get other text file outside of templates directory. how can I send content of requested file in veiw.py ??
I think I cant use render_to_response()..
I need your help:(
Simething like this in your url:
url(r'^static/mymedia/' , 'myproject.views.get_file'),
Something like this in your views:
def get_file(request):
current_directory='/home/arpit/myproject/'
f=open(current_directory+request.path)
return HttpResponse(f.read(),mimetype='text/plain')
I have been developing a Firefox extension using the Addon SDK and need to load some data that is stored in the same package, as a separate file: "data.json". It needs to be loaded from a page script, i.e. "loader.js" which is included in the "panel.html" using the script src tags.
The structure is like this:
+data
panel.html
panel.js
loader.js
data.json
...
+lib
main.js
...
panel.html has:
<script type="text/javascript" src="loader.js"></script>
Initially we stored the data simply into a js file as "data.js" and included from the "panel.html" using script src tags and it worked without any problems. However when we submitted the add-on to the Mozilla Addon site, this was addressed as one of the issues to fix, saying that we need to use a non-executable format, such as a JSON file to make it more safe.
Now the problem seems like "loader.js" is not allowed to make a AJAX request to "data.json". (Using the JQuery $.ajax() call returns with no success, giving the error code 0) So the solution I have been thinking of is to load "data.json" from "main.js" using the SDK's request() function and somehow pass it to the "loader.js", the page script. But that seems to be complicated since, as far as I understand, the data needs to be first sent to a content script, and then from there to the page script. And this needs to be happen when the page script is loading! I am confused about this since I am not sure if I am missing a much more practical solution, or is it really something complicated what I am trying to do, simply loading local JSON data in the package into a local page script?
Here's an example on the Add-on Builder that explores and approach to this.
First off, you can load the json file from data and parse it using self.data.load:
let data = require('self').data;
let taps_data = JSON.parse(data.load('taps.json'));
This loads synchronously, so it isn't something you want to do often, in the example it would only happen when the add-on firsst becomes active in a browsing session.
Next, you would use content scripts and message passing to pass the data in to the panel.
In the main.js script:
panel.on('show', function() {
if (!loaded)
panel.port.emit('taps-data', taps_data);
});
In the content script:
self.port.on('taps-data', function(data) {
$('#list').html('');
data.forEach(function(item) {
$('#list').append('<div>'+ item.name +'</div>');
});
self.port.emit('taps-loaded');
});
I do a bit of extra work to make sure I'm only emitting the data once. The data, FYI, is saved from the live beer keg data api from my local pub.
Here is my situation:
Im creating a widget that site admins can embed in their site and the data are stored in my server. So the script basically has to make an ajax request to a php file in my server to update the database. Right? Right :)
The ajax request works excellent when i run it in my local server but it does not work when the php file is on my ONLINE server.
This is the code im using:
var url = "http://www.mydomain.net/ajax_php.php";
var params = "com=ins&id=1&mail=mymail#site.net";
http.async = true;
http.open("POST", url, true);
http.onreadystatechange = function() {
if(http.readyState == 4 && http.status == 200) {
//do my things here
alert( http.responseText );
}
}
http.send(params);
In firebug it shows: http://www.mydomain.net/ajax_php.php 200 OK X 600ms.
When i check the ajax responnseText I always get a Status:0
Now my question is: "Can i do cross-domain ajax requests by default? Might this be a cross-domain ajax problem? Since it works when the requested file resides in my local server but DOESN'T work when the requested file is in another server, im thinking ajax requests to another remote server might be denied? Can you help me clear on this?
Thanks..
Cross-domain requests are not directly allowed. However, there is a commonly-used technique called JSONP that will allow you to avoid this restriction through the use of script tags. Basically, you create a callback function with a known name:
function receiveData(data) {
// ...
}
And then your server wraps JSON data in a function call, like this:
receiveData({"the": "data"});
And you "call" the cross-domain server by adding a script tag to your page. jQuery elegantly wraps all of this up in its ajax function.
Another technique that I've had to use at times is cross-document communication through iframes. You can have one window talk to another, even cross-domain, in a restricted manner through postMessage. Note that only recent browsers have this functionality, so that option is not viable in all cases without resorting to hackery.
You're going to need to have your response sent back to your client via a JSONP call.
What you'll need to do is to have your request for data wrapped in a script tag. Your server will respond with your data wrapped in a function call. By downloading the script as an external resource, your browser will execute the script (just like adding a reference to an external JS file like jQuery) and pass the data to a known JS method. Your JS method will then take the data and do whatever you need to do with it.
Lots of steps involved. Using a library like jQuery provides a lot of support for this.
Hope this helps.