CODEWITHSUNDEEP
javascripthtmlfiledownloadfileapi
guest271314
guest271314

Reputation: 1

How to download a file without using <a> element with download attribute or a server?

According to caniuse the download attribute of <a> element is supported at Microsoft Edge build 10547+, but not IE or Safari.

How to download a file object without using <a> element with download attribute set or a server?

Upvotes: 14

Views: 28816

Answers (6)

guest271314
guest271314

Reputation: 1

You can use data URI data:[<mediatype>][;base64],<data> representation of file either created manually or utilizing FileReader(), .readAsDataURL(), with MIME type set to application/octet-stream, encodeURIComponent(), window.open()

<script>
  var file = "data:application/octet-stream,"
             + encodeURIComponent("<!DOCTYPE html>"
             + "<html><body>"
             + "<div>abc</div>"
             + "</body></html>");
  var saveFile = window.open(file, "_self");     
</script>


<script>
  var blob = new Blob(["abc"], {type:"text/plain"});
  var reader = new FileReader();
  reader.addEventListener("load", function(e) {
    // replace existing `MIME` type with `application/octet-stream`
    var file = "data:application/octet-stream;" 
                + e.target.result.split(/;/)[1];
    var saveFile = window.open(file, "_self");
  });
  reader.readAsDataURL(blob)
</script>

plnkr http://plnkr.co/edit/IS1OC0laRwL3BuuF9zay?p=preview

Upvotes: 1

Leo Farmer
Leo Farmer

Reputation: 7900

There are a number of ways of triggering a download. Following are a few:

Use a form:

<form method="get" action="mydoc.doc">
<button type="submit">Download</button>
</form>

Use javascript:

<button type="submit" onclick="window.open('mydoc.doc')">Download</button>

Upvotes: 18

Pradeep Kumar Das
Pradeep Kumar Das

Reputation: 891

If you're using server-side then follow the form submission mechanism to render the page. In MVC we can use below code

Html

  @using (Html.BeginForm("GetAttachment", "User", FormMethod.Post))
                {

                    <button type="submit">Download</button>   
                }

MVC Controller

public ActionResult GetAttachment()
{
   string filename = "File.pdf";
string filepath = AppDomain.CurrentDomain.BaseDirectory + "/Path/To/File/" + filename;
byte[] filedata = System.IO.File.ReadAllBytes(filepath);
string contentType = MimeMapping.GetMimeMapping(filepath);

var cd = new System.Net.Mime.ContentDisposition
{
    FileName = filename,
    Inline = true,
};

Response.AppendHeader("Content-Disposition", cd.ToString());

return File(filedata, contentType);
}

Upvotes: -2

Myst
Myst

Reputation: 19221

Although I support @LeoFarmer's answer, I would like to offer two "hackable" approaches:

  1. If the file is very small, you can use a with the href='data:[<mediatype>][;base64],<data>'.

    This could allow you to add content disposition in the mediatype, emulating an HTTP header. This hack is also not as portable as one might hope.

  2. On small to medium files, it's possible to download the file using AJAX, and then use the Javascript File API to prompt for file saving (the API doesn't support saving, but it's easy to convert the data to a data URL).

    If you want to avoid the Javascript File API, you can try emulating an anchor click, as suggested here.

Again, as pointed out by Leo Farmer, these solutions can't promise that the browser won't open the file in a new tab instead of saving it to the disk, but I think it's safe to say that all users will be able to gracefully degrade to a cmd+S or ctrl+S keyboard shortcut :-)

Upvotes: 4

padr
padr

Reputation: 405

Use FileSaver.js

It supports all the commonly used browsers.

Just include:

<script type="text/javascript" src="FileSaver.min.js"></script>

and use it like:

var file = new File(["Hello, world!"], "hello world.txt", {type: "text/plain;charset=utf-8"});
saveAs(file);

Note: To make it work also in Safari < 6, Opera < 15 and FireFox < 20 you need to include Blob.js as a dependency.

Upvotes: 3

Jahid Hasan
Jahid Hasan

Reputation: 224

You may do this using both download attribute and jquery. download attribute don't support in ie and safari/ios. So you may use jquery to do that

 $('.download').click(function(e) {
    e.preventDefault();  //stop the browser from following
    window.location.href = 'uploads/file.doc';
});

<a href="no-script.html" class="download">Download</a>

Upvotes: 2

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