I am implementing a drag'n'drop code for uploading images. I'm a newbie on this technology/API.
I'm using the drag'n'drop API of the HTML5. I also use Apache as http server and node.js as websocket server. I found lots of tutorials for the client side implementation.
This is maybe a silly question, but what about the server side? I guess I have to implement a code on server side to handle the incoming image's upload and storage...
Any ideas?Or links?
Thanks
EDIT
I will use these APIs : drag'n'drop, FormData, XHR progress event and FileReader. I will create code based on this tutorial. I have not implemented anything specific yet, I'm still experimenting.
The file saving on the server side is used as normally!
After using drag&drop you will get the file-objects in javascript and you can do what you want with them, either XHR-post them, use them in a normal form-POST or convert to a data-URI and post it to the server as base64 text.
i.e
element.ondrop = function(ev) {
var files = ev.dataTransfer.files
// post the files via XHR POST
var formData = new FormData()
// im lazy, use a supported loop
for (file of files) {
formData.append("file", file)
}
var req = new XMLHttpRequest()
req.open('POST', '/saveimage/')
req.send(formData)
}
Will post the files just as you had used a normal non-drag and drop action.
For a better answer on how to save files we need some info about what language and framework your website uses.
Related
I am new to web development and need your help to figure out how to use the form in HTML and use the data to populate the said field in a word document. Any advice on how to approach this problem is highly appreciated. It would really help if you could post a live example for the below. Please,do let me know if any further explanation is required.
As a new developer, I want to advise you that you are getting into some challenging territory here and many of the solutions might require some heavy experience with programming and MS Word. In this forum, there are many options you can try, but from what I gather you will need to learn about macros.
The second option you could try are some services that will do this for you for a fee. Here are two options. Check out Formstack or Jotform
If you use this type of service, you would create a form action within your html code that will merge the data from the form into the Microsoft Word Document using merge tags.
The third option you can try is using Javascript within the form to populate the Word Document. The code would look more like this:
function Export2Word(element, filename = ''){
var preHtml = "<html xmlns:o='urn:schemas-microsoft-com:office:office' xmlns:w='urn:schemas-microsoft-com:office:word' xmlns='http://www.w3.org/TR/REC-html40'><head><meta charset='utf-8'><title>Export HTML To Doc</title></head><body>";
var postHtml = "</body></html>";
var html = preHtml+document.getElementById(element).innerHTML+postHtml;
var blob = new Blob(['\ufeff', html], {
type: 'application/msword'
});
// Specify link url
var url = 'data:application/vnd.ms-word;charset=utf-8,' + encodeURIComponent(html);
// Specify file name
filename = filename?filename+'.doc':'document.doc';
// Create download link element
var downloadLink = document.createElement("a");
document.body.appendChild(downloadLink);
if(navigator.msSaveOrOpenBlob ){
navigator.msSaveOrOpenBlob(blob, filename);
}else{
// Create a link to the file
downloadLink.href = url;
// Setting the file name
downloadLink.download = filename;
//triggering the function
downloadLink.click();
}
document.body.removeChild(downloadLink);
}
Export HTML Table Data to Excel using JavaScript
HTML Content:
Wrap the HTML content in a container you want to export to MS Word document (.doc).
<div id="exportContent">
<!-- Your content here -->
</div>
Last option would be using PHP, and I recommend watching this video by CodexWorld and reviewing the post that goes along with it here. This is a challenging concept, so I would encourage you to take your time.
Hopefully this will help and best of luck.
Well, I don't know how to exactly do that, I am also a beginner like you. What seems to help you might be connecting your form with Google Sheets. The Google Spread Sheet will store all data submitted via your form. You can then use this data wherever you want.
There is an open source project for this task, you can do that by following the steps stated here: https://github.com/dwyl/learn-to-send-email-via-google-script-html-no-server
You can see it in action here: https://nisootech.vercel.app/#contact-me
There are two parts in your application
Enabling user to input the values in frontend. Which you can build using any frontend technology stack eg: HTML and Plain Javascript(Required for calling the Services), React JS, Angular etc.
Backend Service which will basically does the heavy work
Receiving the input from user.
Creating Word file using any libraries such as
Generate word files using Apache POI ,
Using Node.js to generate dynamic word document using Database value
Downloading the file after its completely generated using the values supplied by user.
download a file from Spring boot rest service
how to download file in react js
For the Backend service you can use technologies like Java and Springboot, Python, Node Js etc.
Building Restful webservices using spring
Use Technology in which you are more comfortable and start building. These Links and documentation you can use to start from basic.
Suggest you to breakdown your problems focus on each specific areas and do the development as per your smaller problems and integrate them later.
I need to have predefined scripts, accessible from chrome content_script, that could be updated automatically from given URL.
Exactly what i do:
I have content_script.js. Inside it, i`d like to create iframe for current page from predefined html+css+js.Sometimes html or css or js can be changed. I want to avoid updating extension, instead, each time user have internet, he could load fresh html+css+js for further offline usage.
So, how to read and write some internal files within extension from content script (or delegate this task to background script)?
You can use HTML5 Filesystem to have a read/write place for files, or just store it as strings in chrome.storage (with "unlimitedStorage" permission as needed) for later reuse.
This code can then be executed in a content script using executeScript, or, if you enable 'unsafe-eval' for the extension CSP, in the main script (which is dangerous, and should be avoided in most cases).
Note that this Filesystem API has a warning that's it's only supported in Chrome, but that shouldn't be a problem (Firefox / WebExtensions platform explicitly reject self-update mechanisms).
You can do read extension file contents, but you can't write to extension folder since it is sandboxed.
To read an extension file, you can just send Ajax call using chrome.runtime.getURL("filepath") as url
var xhr = new XMLHttpRequest();
xhr.open('GET', chrome.runtime.getURL('your file path'), true);
xhr.onreadystatechange = function() {
if (chr.readyState === XMLHttpRequest.DONE && xhr.status === 200) {
var text = xhr.responseText;
// Do what you want using text
}
};
xhr.send();
Is there any known and consolidated alternative for defining a new Angular scope reading data from outside?
I am working on a demo that should make available a standalone html page which reads the data from the same html file position, and on client machines without any webserver.
This because the HTML is generated on the fly from a pdf.
Do you have any idea?
In my working code below I should change $http.get('data.json'.. to avoid the Google restriction (on Firefox my sample is working fine).
<script>
var isisApp = angular.module('isisApp', []);
isisApp.controller('ISISListCtrl', function($scope, $http) {
$http.get('data.json').success(function(data) {
$scope.IsisDocument = data;
etc.....
and this is the error I get from Chrome:
XMLHttpRequest cannot load file:///C:/temp/data.json. Cross origin requests are only supported for HTTP. angular.js:8081
Error: A network error occurred.
Thanks in advance
Fabio
If you want to test your code, while developing, you have two options:
Use a local web server. You could use Node.js platform, using expressjs.
Start Chrome from the terminal with the –allow-file-access-from-files option
I'm trying to get dojo to show Json data that comes from a remote web service. I need to be clear though - the web server hosting the html/dojo page I access isn't the same server as the one that's running the web service that returns the json data - the web service server just can't serve html pages reliably (don't ask!!).
As a test I move the page into the same web server as the web service and the below works. As soon as I move it back so that the html/dojo is served from Apache (//myhost.nodomain:82 say) and the web service sending the json is "{target:http://myhost.nodomain:8181}", then it stops working.
I've used FFox to look at the network & I see the web service being called ok, the json data is returned too & looks correct (I know it is from the previous test), but the fields are no longer set. I've tried this with DataGrid and the plain page below with the same effects.
Am I tripping up over something obvious???
Thanks
require([
"dojo/store/JsonRest",
"dojo/store/Memory",
"dojo/store/Cache",
"dojox/grid/DataGrid",
"dojo/data/ObjectStore",
"dojo/query",
"dojo/domReady!"
],
function(JsonRest, Memory, Cache, DataGrid, ObjectStore, query) {
var myStore, dataStore, grid;
myStore = JsonRest(
{
target: "http://localhost:8181/ws/job/definition/",
idProperty: "JOB_NAME"
}
);
myStore.query("JOB00001"
).then(function(results) {
var theJobDef = results[0];
dojo.byId("JOB_NAME").innerHTML = theJobDef.JOB_NAME;
dojo.byId("SCHEDULED_DAYS").innerHTML = theJobDef.SCHEDULED_DAYS;
});
}
);
Its true what Frans said about the cross domain restriction but dojo has this link to work around the problem.
require(["dojo/request/iframe"], function(iframe){
iframe("something.xml", {
handleAs: "json"
}).then(function(xmldoc){
// Do something with the XML document
}, function(err){
// Handle the error condition
});
// Progress events are not supported using the iframe provider
});
you can simply use this and the returned data can be inserted into a store and then into the grid.
Are you familiar with the Same Origin Policy:
http://en.wikipedia.org/wiki/Same-origin_policy
Basically it restricts websites to do AJAX requests to other domains than the html page was loaded from. Common solutions to overcome this are CORS and JSON-P. However, remember that these restrictions are made for security reasons.
I'm trying to get sound working on my iPhone game using the Web Audio API. The problem is that this app is entirely client side. I want to store my mp3s in a local folder (and without being user input driven) so I can't use XMLHttpRequest to read the data. I was looking into using FileSystem but Safari doesn't support it.
Is there any alternative?
Edit: Thanks for the below responses. Unfortunately the Audio API is horribly slow for games. I had this working and the latency just makes the user experience unacceptable. To clarify, what I need is sounething like -
var request = new XMLHttpRequest();
request.open('GET', 'file:///./../sounds/beep-1.mp3', true);
request.responseType = 'arraybuffer';
request.onload = function() {
context.decodeAudioData(request.response, function(buffer) {
dogBarkingBuffer = buffer;
}, onError);
}
request.send();
But this gives me the errors -
XMLHttpRequest cannot load file:///sounds/beep-1.mp3. Cross origin requests are only supported for HTTP.
Uncaught Error: NETWORK_ERR: XMLHttpRequest Exception 101
I understand the security risks with reading local files but surely within your own domain should be ok?
I had the same problem and I found this very simple solution.
audio_file.onchange = function(){
var files = this.files;
var file = URL.createObjectURL(files[0]);
audio_player.src = file;
audio_player.play();
};
<input id="audio_file" type="file" accept="audio/*" />
<audio id="audio_player" />
You can test here:
http://jsfiddle.net/Tv8Cm/
Ok, it's taken me two days of prototyping different solutions and I've finally figured out how I can do this without storing my resources on a server. There's a few blogs that detail this but I couldn't find the full solution in one place so I'm adding it here. This may be considered a bit hacky by seasoned programmers but it's the only way I can see this working, so if anyone has a more elegent solution I'd love to hear it.
The solution was to store my sound files as a Base64 encoded string. The sound files are relatively small (less than 30kb) so I'm hoping performance won't be too much of an issue. Note that I put 'xxx' in front of some of the hyperlinks as my n00b status means I can't post more than two links.
Step 1: create Base 64 sound font
First I need to convert my mp3 to a Base64 encoded string and store it as JSON. I found a website that does this conversion for me here - xxxhttp://www.mobilefish.com/services/base64/base64.php
You may need to remove return characters using a text editor but for anyone that needs an example I found some piano tones here - xxxhttps://raw.github.com/mudcube/MIDI.js/master/soundfont/acoustic_grand_piano-mp3.js
Note that in order to work with my example you're need to remove the header part data:audio/mpeg;base64,
Step 2: decode sound font to ArrayBuffer
You could implement this yourself but I found an API that does this perfectly (why re-invent the wheel, right?) - https://github.com/danguer/blog-examples/blob/master/js/base64-binary.js
Resource taken from - here
Step 3: Adding the rest of the code
Fairly straightforward
var cNote = acoustic_grand_piano.C2;
var byteArray = Base64Binary.decodeArrayBuffer(cNote);
var context = new webkitAudioContext();
context.decodeAudioData(byteArray, function(buffer) {
var source = context.createBufferSource(); // creates a sound source
source.buffer = buffer;
source.connect(context.destination); // connect the source to the context's destination (the speakers)
source.noteOn(0);
}, function(err) { console.log("err(decodeAudioData): "+err); });
And that's it! I have this working through my desktop version of Chrome and also running on mobile Safari (iOS 6 only of course as Web Audio is not supported in older versions). It takes a couple of seconds to load on mobile Safari (Vs less than 1 second on desktop Chrome) but this might be due to the fact that it spends time downloading the sound fonts. It might also be the fact that iOS prevents any sound playing until a user interaction event has occured. I need to do more work looking at how it performs.
Hope this saves someone else the grief I went through.
Because ios apps are sandboxed, the web view (basically safari wrapped in phonegap) allows you to store your mp3 file locally. I.e, there is no "cross domain" security issue.
This is as of ios6 as previous ios versions didn't support web audio api
Use HTML5 Audio tag for playing audio file in browser.
Ajax request works with http protocol so when you try to get audio file using file://, browser mark this request as cross domain request. Set following code in request header -
header('Access-Control-Allow-Origin: *');