I am downloading an image when a div is clicked by using...
document.location.href = save_canvas.toDataURL("image/jpeg").replace("image/jpeg", "image/octet-stream");
This is working but the image that downloads has no extension and is just called 'download'
I have tried setting the name like this...
document.location.download = "myfile.jpg";
document.location.href = save_canvas.toDataURL("image/jpeg").replace("image/jpeg", "image/octet-stream");
But it is having no effect, where am i going wrong?
The download attribute is not part of the Location object as document.location holds, only for the HTML anchor (A) tags (except in IE).
Depending on browser and version you could instead try to convert canvas into a Blob object, then to File in order to set a filename, and serve that as URL via URL.createObjectURL(). Also here, toBlob() is not supported in IE (but you can polyfill toBlob(), and use msSaveBlob instead).
(and you would also want to replace mime-type's "image" with "application" for mime-type (e.g. "application/octet-stream"). )
c.toBlob(function(blob) {
var file = new File([blob], "test.png", {type: "application/octet-stream"});
document.location.href = URL.createObjectURL(file);
})
A save request with PNG and filename should appear when running this code...
<canvas id=c></canvas>
Optionally, try the FileSaver.js library which deals with many special cases.
Related
Some PDF files won't render in Chrome browser but will render fine in Firefox. All files render fine in all browsers if emeded directly.
<object id="content-view" :data="content_view.base64" type="application/pdf"></object>
The confusing part is that the problem is only for some files and not all. Files are stored in a folder that is not public and that's why they are served as base64 for the user to view.
I tested the problematic files by using online base64 decoders and I get the same result. Rendered in FF, not rendered in Chrome.
I cannot share any of the PDF files. They are all from the same source, scanned from the same device, PDF version 1.4, 4 pages.
I have tried:
using iframe, embed and object (same result)
unblocking Insecure content in Chrome site settings
opening and re-saving in Adobe Acrobat
using online PDF analyzers to see if any problems present (none found)
I had the exact same issue. I noticed that some of the PDFs that are more than 1MB isn't loading.
I found a solution here: Open base64 encoded pdf file using javascript. Issue with file size larger than 2 MB
Need to change the Base64 string to a BLOB. Then create a URL to be used for iframe src.
Here is the code:
base64PDFToBlobUrl( base64 ) {
const binStr = atob( base64 );
const len = binStr.length;
const arr = new Uint8Array(len);
for (let i = 0; i < len; i++) {
arr[ i ] = binStr.charCodeAt( i );
}
const blob = new Blob( [ arr ], { type: 'application/pdf' } );
const url = URL.createObjectURL( blob );
return url;
}
This will return a url that you can put inside your iframe, embed or object src. This way, you can still load the PDF in a page without opening it in another tab.
Rather than use the browsers native PDF renderer, you could use the JS one written by Mozilla.
ViewerJS provides a nice interface to this and if you want to embed it fullsize in a page, then you can place it in an iframe and control that with iFrame-resizer.
Instead of opening the PDF file in HTML object element, open it in a new window using Blob URL.
Please refer
Creating a BLOB from a Base64 string in JavaScript
to convert Base64 to Blob
My page generates a URL like this: "blob:http%3A//localhost%3A8383/568233a1-8b13-48b3-84d5-cca045ae384f" How can I convert it to a normal address?
I'm using it as an <img>'s src attribute.
A URL that was created from a JavaScript Blob can not be converted to a "normal" URL.
A blob: URL does not refer to data the exists on the server, it refers to data that your browser currently has in memory, for the current page. It will not be available on other pages, it will not be available in other browsers, and it will not be available from other computers.
Therefore it does not make sense, in general, to convert a Blob URL to a "normal" URL. If you wanted an ordinary URL, you would have to send the data from the browser to a server and have the server make it available like an ordinary file.
It is possible convert a blob: URL into a data: URL, at least in Chrome. You can use an AJAX request to "fetch" the data from the blob: URL (even though it's really just pulling it out of your browser's memory, not making an HTTP request).
Here's an example:
var blob = new Blob(["Hello, world!"], { type: 'text/plain' });
var blobUrl = URL.createObjectURL(blob);
var xhr = new XMLHttpRequest;
xhr.responseType = 'blob';
xhr.onload = function() {
var recoveredBlob = xhr.response;
var reader = new FileReader;
reader.onload = function() {
var blobAsDataUrl = reader.result;
window.location = blobAsDataUrl;
};
reader.readAsDataURL(recoveredBlob);
};
xhr.open('GET', blobUrl);
xhr.send();
data: URLs are probably not what you mean by "normal" and can be problematically large. However they do work like normal URLs in that they can be shared; they're not specific to the current browser or session.
another way to create a data url from blob url may be using canvas.
var canvas = document.createElement("canvas")
var context = canvas.getContext("2d")
context.drawImage(img, 0, 0) // i assume that img.src is your blob url
var dataurl = canvas.toDataURL("your prefer type", your prefer quality)
as what i saw in mdn, canvas.toDataURL is supported well by browsers. (except ie<9, always ie<9)
For those who came here looking for a way to download a blob url video / audio, this answer worked for me. In short, you would need to find an *.m3u8 file on the desired web page through Chrome -> Network tab and paste it into a VLC player.
Another guide shows you how to save a stream with the VLC Player.
UPDATE:
An alternative way of downloading the videos from a blob url is by using the mass downloader and joining the files together.
Download Videos Part
Open network tab in chrome dev tools
Reload the webpage
Filter .m3u8 files
Look through all filtered files and find the playlist of the '.ts' files. It should look something like this:
You need to extract those links somehow. Either download and edit the file manually OR use any other method you like. As you can see, those links are very similar, the only thing that differs is the serial number of the video: 's-0-v1-a1.ts', 's-1-v1-a1.ts' etc.
https://some-website.net/del/8cf.m3u8/s-0-v1-a1.ts
https://some-website.net/del/8cf.m3u8/s-1-v1-a1.ts
https://some-website.net/del/8cf.m3u8/s-2-v1-a1.ts
and so on up to the last link in the .m3u8 playlist file. These .ts files are actually your video. You need to download all of them.
For bulk downloading I prefer using the Simple Mass Downloader extension for Chrome (https://chrome.google.com/webstore/detail/simple-mass-downloader/abdkkegmcbiomijcbdaodaflgehfffed)
If you opt in for the Simple Mass Downloader, you need to:
a. Select a Pattern URL
b. Enter your link in the address field with only one modification: that part of the link that is changing for each next video needs to be replaced with the pattern in square brackets [0:400] where 0 is the first file name and 400 is the last one. So your link should look something like this https://some-website.net/del/8cf.m3u8/s-[0:400]-v1-a1.ts.
Afterwards hit the Import button to add these links into the Download List of Mass Downloader.
c. The next action may ask you for the destination folder for EACH video you download. So it is highly recommended to specify the default download folder in Chrome Settings and disable the Select Destination option in Chrome Settings as well. This will save you a lot of time! Additionally you may want you specify the folder where these files will go to:
c1. Click on Select All checkbox to select all files from the Download List.
c2. Click on the Download button in the bottom right corner of the SMD extension window. It will take you to next tab to start downloading
c3. Hit Start selected. This will download all vids automatically into the download folder.
That is it! Simply wait till all files are downloaded and you can watch them via the VLC Player or any other player that supports the .ts format. However, if you want to have one video instead of those you have downloaded, you need to join all these mini-videos together
Joining Videos Part
Since I am working on Mac, I am not aware of how you would do this on Windows. If you are the Windows user and you want to merge the videos, feel free to google for the windows solution. The next steps are applicable for Mac only.
Open Terminal in the folder you want the new video to be saved in
Type: cat and hit space
Open the folder where you downloaded your .ts video. Select all .ts videos that you want to join (use your mouse or cmd+A)
Drag and drop them into the terminal
Hit space
Hit >
Hit Space
Type the name of the new video, e.g. my_new_video.ts. Please note that the format has to be the same as in the original videos, otherwise it will take long time to convert and even may fail!
Hit Enter. Wait for the terminal to finish the joining process and enjoy watching your video!
Found this answer here and wanted to reference it as it appear much cleaner than the accepted answer:
function blobToDataURL(blob, callback) {
var fileReader = new FileReader();
fileReader.onload = function(e) {callback(e.target.result);}
fileReader.readAsDataURL(blob);
}
I'm very late to the party.
If you want to download the content you can simply use fetch now
fetch(blobURL)
.then(res => res.blob())
.then(blob => /*do what you want with the blob here*/)
Here the solution:
let blob = new Blob(chunks, { 'type' : 'video/mp4;' });
let videoURL = window.URL.createObjectURL(blob);
const blobF = await fetch(videoURL).then(res => res.blob())
As the previous answer have said, there is no way to decode it back to url, even when you try to see it from the chrome devtools panel, the url may be still encoded as blob.
However, it's possible to get the data, another way to obtain the data is to put it into an anchor and directly download it.
<a href="blob:http://example.com/xxxx-xxxx-xxxx-xxxx" download>download</a>
Insert this to the page containing blob url and click the button, you get the content.
Another way is to intercept the ajax call via a proxy server, then you could view the true image url.
I need to set some headers when getting an image. The img src attribute does not allow this, so I'm using an XHR request to get the image. However, when I set the src attribute on the img tag after that request completes, it looks like the request is triggered again. Is there a way to cache the image and not trigger the second request?
Sample Code:
$(document).ready(function() {
var url = 'https://i.imgur.com/bTaDhpy.jpg'
var file = $.get(url);
file.then(function(data) {
$('#foo').attr('src', url);
});
});
JS Fiddle: https://jsfiddle.net/mehulkar/o4Lcs5Lo/
Note: my question is not about how to set the appropriate headers in the xhr request. My question is how to not trigger another GET from the setting of the src attribute and use the response from the XHR to display the image.
Use the $.ajax for this:
var myImg = $('#foo'),
mySrc = 'https://i.imgur.com/bTaDhpy.jpg';
$.ajax({
url: mySrc,
type: "GET",
headers: {
"X-TOKEN": 'xxxxx'
}
}).done(function() {
myImg.attr('src', mySrc); // set the image source
}).fail(function() {
myImg.hide(); // or something other
});
I cannot comment here due to reputation points, but here is what I've found on this.
I have a local html page that I'm executing via file:///
I can use a $.get to dynamically pull svg files into a variable. The debugger shows this as if it were a standard html node <svg. (I'm using Firefox Developer, but also in Firebug I see the svg file as a node.).
So At this point I have an empty <img that I want to set to my svg file I just don't know how to set the src attribute to the actual document itself. I suppose I could encode to base64.. You might be able to set it using the debugger itself. I couldn't get this to work reliably. Another avenue (for me since I'm using svg) is to clone the object then write it node for node. If you're not using svg perhaps there is some similar hack you could conduct with canvas? Load the image as a sprite then read the colors and set pixels?
I want make display word file in pop window using mvc 4 razor. the file has been taken from specific path and the file already stored in my project.
If you need a popup with smaller size than the full-screen window, you could try with some javascript:
fileDownloadLink variable is your download link, pointing to the Action method in your controller
The second and third arguments are explained in MDN reference for window.open function here MDN: Window.open
window.open(fileDownloadLink, 'insertPopupNameHere', 'width=400,height=400')
Otherwise you can just use an anchor tag with atribute target="_blank" (this will just open new tab in most browsers).
Preview File
The code for your action method:
//Insert your mime type here, if you know it
var fileType = "application/octet-stream";
if (inline)
{
var showInlineHeader = new System.Net.Mime.ContentDisposition
{
// for example foo.bak
FileName = result.FileName,
// always prompt the user for downloading, set to true if you want
// the browser to try to show the file inline
Inline = inline,
};
Response.AppendHeader("Content-Disposition", showInlineHeader.ToString());
return File(result.Content, fileType);
}
I have added to my method the if statement in order to directly download files that I don't want to be previewed.
Original answer for forcing preview if availabale, taken from Returning a file to View/Download in MVC
I have a basic idea of HTML. I want to create the download link in my sample website, but I don't have idea of how to create it. How do I make a link to download a file rather than visit it?
In modern browsers that support HTML5, the following is possible:
<a href="link/to/your/download/file" download>Download link</a>
You also can use this:
Download link
This will allow you to change the name of the file actually being downloaded.
This answer is outdated. We now have the download attribute. (see also this link to MDN)
If by "the download link" you mean a link to a file to download, use
Download
the target=_blank will make a new browser window appear before the download starts. That window will usually be closed when the browser discovers that the resource is a file download.
Note that file types known to the browser (e.g. JPG or GIF images) will usually be opened within the browser.
You can try sending the right headers to force a download like outlined e.g. here. (server side scripting or access to the server settings is required for that.)
In addition (or in replacement) to the HTML5's <a download attribute already mentioned,
the browser's download to disk behavior can also be triggered by the following http response header:
Content-Disposition: attachment; filename=ProposedFileName.txt;
This was the way to do before HTML5 (and still works with browsers supporting HTML5).
A download link would be a link to the resource you want to download. It is constructed in the same way that any other link would be:
Link
Link to installer
To link to the file, do the same as any other page link:
link text
To force things to download even if they have an embedded plugin (Windows + QuickTime = ugh), you can use this in your htaccess / apache2.conf:
AddType application/octet-stream EXTENSION
This thread is probably ancient by now, but this works in html5 for my local file.
For pdfs:
<p>test pdf</p>
This should open the pdf in a new windows and allow you to download it (in firefox at least). For any other file, just make it the filename. For images and music, you'd want to store them in the same directory as your site though. So it'd be like
<p><a href="images/logo2.png" download>test pdf</a></p>
There's one more subtlety that can help here.
I want to have links that both allow in-browser playing and display as well as one for purely downloading. The new download attribute is fine, but doesn't work all the time because the browser's compulsion to play the or display the file is still very strong.
BUT.. this is based on examining the extension on the URL's filename!You don't want to fiddle with the server's extension mapping because you want to deliver the same file two different ways. So for the download, you can fool it by softlinking the file to a name that is opaque to this extension mapping, pointing to it, and then using download's rename feature to fix the name.
<a target="_blank" download="realname.mp3" href="realname.UNKNOWN">Download it</a>
<a target="_blank" href="realname.mp3">Play it</a>
I was hoping just throwing a dummy query on the end or otherwise obfuscating the extension would work, but sadly, it doesn't.
You can use in two ways
<a href="yourfilename" download>Download</a>
it will download file with original name In Old Browsers this option was not available
2nd
Download
Here You have option to rename your file and download with a different name
The download attribute is new for the <a> tag in HTML5
<a href="http://www.odin.com/form.pdf" download>Download Form</a>
or
Download Form
I prefer the first one it is preferable in respect to any extension.
If you host your file in AWS, this may work for you. The code is very easy to understand. Because the browser doesn't support same-origin download links, 1 way to solve it is to convert the image URL to a base64 URL. Then, you can download it normally.
var canvas = document.createElement("canvas")
var ctx = canvas.getContext('2d')
var img = new Image()
img.src = your_file_url + '?' + new Date().getTime();
img.setAttribute('crossOrigin', '')
var array = your_file_url.src.split("/")
var fileName = array[array.length - 1]
img.onload = function() {
canvas.width = img.naturalWidth
canvas.height = img.naturalHeight
ctx.drawImage(img,
0, 0, img.naturalWidth, img.naturalHeight,
0, 0, canvas.width, canvas.height)
var dataUrl = canvas.toDataURL("image/png", 1)
var a = document.createElement('a')
a.href = dataUrl
a.download = fileName
document.body.appendChild(a)
a.click()
document.body.removeChild(a)
}
Like this
Link name
So a file name.jpg on a site example.com would look like this
Image
i know i am late but this is what i got after 1 hour of search
<?php
$file = 'file.pdf';
if (! file) {
die('file not found'); //Or do something
} else {
if(isset($_GET['file'])){
// Set headers
header("Cache-Control: public");
header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=$file");
header("Content-Type: application/zip");
header("Content-Transfer-Encoding: binary");
// Read the file from disk
readfile($file); }
}
?>
and for downloadable link i did this
Download PDF