Downloading files is a common task for web applications. These files could be some PDF, ZIP or any other binary or text-based file that you want to make accessible to your users. Here's how you can download files in Angular either with a rather simple link or JavaScript-based for more control and progress indication.
You'll use an anchor tag pointing to the file with the href attribute. The download attribute informs the browser that it shouldn't follow the link but rather download the URL target. You can also specify its value in order to set the name of the file being downloaded.
You can bind any of these attributes with Angular in order to set the URL and filename dynamically:. Older browsers, like the Internet Explorer, might not recognize the download attribute. If there's no download attribute, the filename for your download will solely depend on the HTTP header Content-Disposition sent by the server that's providing the file. The information from this header might also take precedence even if the download attribute is present.
A link-based solution conforms well to HTML standards and lets the browser do most of the work. However, if you want more control over the download and would like to display some custom progress indicator you can also download files via Angular's HttpClient. A file is best represented as a Blob in the browser:. The Blob object represents a blob, which is a file-like object of immutable, raw data -- MDN web docs. By specifying the responseType option we can perform a GET request returning a blob representing the downloaded file.
Let's assume we've got a designated DownloadService doing just that:. A component would then be able to call this service, subscribe to the corresponding observable and eventually save the file like this:. Here, we're creating an anchor tag programmatically when the blob arrives. With URL. Finally, we click the link like the user would've done with a regular browser download link. After the file is downloaded, we'll discard the blob by revoking the object URL we created. This approach is pretty verbose though and might not work smoothly for every browser.
Therefore I'd advise you to use the popular library FileSaver. The saving then becomes a one-liner:. If you don't like adding a dependency for this and would prefer to use the manual approach shown before, you might as well refactor the code for saving the blob into a separate service. You can also create a custom injection token for URL - also see below how we'll do this for FileSaver. By setting the option observe to events while making an HTTP request, we won't just receive the final response body of the request but also get access to intermediate HTTP events.
Go through the link Creating Angular Project to create a new project. Make sure you give the project name as angular-file-download. For Angular 11 , you will find another option to set whether you want to use stricter type or not.
Here I am using stricter type and later I will show you how to use stricter type for response and error. Remember the file extension ts service. Service is one of fundamental blocks of every Angular application. Service is just a TypeScript class with or even without Injectable decorator. Once you create the service class you need to register it under app. Injectable is a decorator that has a property providedIn. When the service is provided at root level, Angular creates a single, shared instance of service and injects into any class that needs it.
Registering the provider in the Injectable metadata also allows Angular to optimize an application by removing the service if it is not used. If you are not using stricter type then your code should be working fine as it is working for Angular First replace the line this. I am also accepting response as Blob Binary Large Object. You may also specify any value from supporting values, such as, json, blob, arraybuffer, text.
You can have a look for more details on response type. I was facing this same case today, I had to download a pdf file as an attachment the file shouldn't be rendered in the browser, but downloaded instead.
To achieve that I discovered I had to get the file in an Angular Blob , and, at the same time, add a Content-Disposition header in the response. Well, I wrote a piece of code inspired by many of the above answers that should easily work in most scenarios where the server sends a file with a content disposition header, without any third-party installations, except rxjs and angular. As you can see, it's basically pretty much the average backend call from angular, with two changes.
Once the file is fetched from the server, I am in principle, delegating the entire task of saving the file to the helper function, which I keep in a separate file, and import into whichever component I need to.
There, no more cryptic GUID filenames! We can use whatever name the server provides, without having to specify it explicitly in the client, or, overwrite the filename provided by the server as in this example.
Also, one can easily, if need be, change the algorithm of extracting the filename from the content-disposition to suit their needs, and everything else will stay unaffected - in case of an error during such extraction, it will just pass 'null' as the filename. As another answer already pointed out, IE needs some special treatment, as always.
But with chromium edge coming in a few months, I wouldn't worry about that while building new apps hopefully. There is also the matter of revoking the URL, but I'm kinda not-so-sure about that, so if someone could help out with that in the comments, that would be awesome. You may also download a file directly from your template where you use download attribute and to [attr.
This simple solution should work on most browsers. This answer suggests that you cannot download files directly with AJAX, primarily for security reasons. So I'll describe what I do in this situation,. Add href attribute in your anchor tag inside the component.
Do all following steps in your component. If a tab opens and closes without downloading anything, i tried following with mock anchor link and it worked. You can return a Blob object from the server and create an anchor tag and set the href property to an object URL created from the Blob. Now clicking on the anchor will download the file. You can set the file name as well.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. How do I download a file with Angular2 or greater Ask Question. Asked 5 years, 9 months ago. Active 1 month ago. Viewed k times. Basil 1, 12 12 silver badges 19 19 bronze badges. You cannot download large files with this method.
You will hit the memory limit per tab. This may be as low as GB. For large file downloads you need to specify a new tab e. I don't think there's a clean way to get around the large file size limitation with Ajax-style requests. Add a comment. Active Oldest Votes. One of the many ways that exist to solve this is as follows: this. Amr ElAdawy 3, 5 5 gold badges 32 32 silver badges 49 49 bronze badges. Alejandro Corredor Alejandro Corredor 2, 1 1 gold badge 8 8 silver badges 6 6 bronze badges.
What is this. Burjua the getReport returns a this. The issue I'm having is that the window opens and closes immediately not downloading the file — Braden Brown. How can we set file name in here? I've used the above code for downloading a file from API response but i'm getting some error in creating the Blob part "Type response is not assignable to type Blobpart".
Kindly help if anyone knows this issue — knbibin. Show 10 more comments. Try this! Hector Cuevas Hector Cuevas 1, 1 1 gold badge 6 6 silver badges 3 3 bronze badges. I used step 2 in combination with the answer from Alejandro and it worked without the need to install file-saver Thank you!
It works perfectly! I wonder if we can get the filename that is defined on the header of the response. Is that possible? This one however is not suitable for big files download. Can someone please tell why this answer is downvoted? The topic is to download a file using angular2. If this method works to do a simple download then it should also be marked as a valid answer. SaurabhShetty, This won't help in case you want to send custom headers, what if you want to send an auth token for example?
If you look into OP question you can see he uses authHttp! I do understand the downvotes, nevertheless this answer solved my issue. If you let the server return the url in some context, the server could prepare the url. The cover could be a url to an image in the server. When calling get Myrecord you let the server return the prepared url Cover , with security token and other headers set.
It is an answer that works. Show 1 more comment. Justin Justin 8 8 silver badges 11 11 bronze badges. How to show the filesize in the browser when the download starts?
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