lilishop-ui/node_modules/_downloadjs@1.4.7@downloadjs/README.md

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2021-06-03 11:47:34 +08:00
# download
========
## Summary
---------
The download() function is used to trigger a file download from JavaScript.
It specifies the contents and name of a new file placed in the browser's download directory. The input can be a URL, String, Blob, or Typed Array of data, or via a dataURL representing the file's data as base64 or url-encoded string. No matter the input format, download() saves a file using the specified file name and mime information in the same manner as a server using a Content-Disposition HTTP header.
## Getting and Using
---------
### Via NPM/Bower
`npm install downloadjs` <br />
`bower install downloadjs`
`require("downloadjs")(data, strFileName, strMimeType);`
### Simple global `download` function via `<script>` include
download(data, strFileName, strMimeType);
### Included via AMD
require(['path/to/file'], function(download) {
download(data, strFileName, strMimeType);
});
### Parameters
---------
* **data** - The Blob, File, String, or dataURL containing the soon-to-be File's contents.
* **strFileName** - The name of the file to be created. Note that older browsers (like FF3.5, Ch5) don't honor the file name you provide, instead they automatically name the downloaded file.
* **strMimeType** - The MIME content-type of the file to download. While optional, it helps the browser present friendlier information about the download to the user, encouraging them to accept the download.
## Example Usage
---------
### Plain Text
#### text string - [live demo](http://pagedemos.com/hw24em95rsfq/output/)
download("hello world", "dlText.txt", "text/plain");
#### text dataURL - [live demo](http://pagedemos.com/r9ywm98s6b29/output/)
download("data:text/plain,hello%20world", "dlDataUrlText.txt", "text/plain");
#### text blob - [live demo](http://pagedemos.com/ckcah2vp8kza/output/)
download(new Blob(["hello world"]), "dlTextBlob.txt", "text/plain");
#### text url - [live demo](http://pagedemos.com/pz6hkyqutjtw/output/)
download("/robots.txt");
#### text UInt8 Array - [live demo](http://pagedemos.com/zuyk46wbkktq/output/)
var str= "hello world", arr= new Uint8Array(str.length);
str.split("").forEach(function(a,b){
arr[b]=a.charCodeAt();
});
download( arr, "textUInt8Array.txt", "text/plain" );
### HTML
#### html string - [live demo](http://pagedemos.com/k7rwq7msu3eb/output/)
download(document.documentElement.outerHTML, "dlHTML.html", "text/html");
#### html Blob - [live demo](http://pagedemos.com/bxehm2fdf3g4/output/)
download(new Blob(["hello world".bold()]), "dlHtmlBlob.html", "text/html");
#### ajax callback - [live demo](http://pagedemos.com/arr2ym74aw8t/output/)
(note that callback mode won't work on vanilla ajax or with binary files)
$.ajax({
url: "/download.html",
success: download.bind(true, "text/html", "dlAjaxCallback.html")
});
### Binary Files
#### image from URL - [live demo](http://pagedemos.com/yvvmxbjrwq7u/output/)
download("/diff6.png");
#### Image via ajax for custom filename - [live demo](http://pagedemos.com/v2848zfgwrju/output/)
var x=new XMLHttpRequest();
x.open( "GET", "/diff6.png" , true);
x.responseType="blob";
x.onload= function(e){download(e.target.response, "awesomesauce.png", "image/png");};
x.send();
## Compatibility
---------
download.js works with a wide range of devices and browsers.
You can expect it to work for the vast majority of your users, with some common-sense limits:
* Devices without file systems like iPhone, iPad, Wii, et al. have nowhere to save the file to, sorry.
* Android support starts at 4.2 for the built-in browser, though chrome 36+ and firefox 20+ on android 2.3+ work well.
* Devices without Blob support won't be able to download Blobs or TypedArrays
* Legacy devices (no a[download]) support can only download a few hundred kilobytes of data, and can't give the file a custom name.
* Devices without window.URL support can only download a couple megabytes of data
* IE versions of 9 and before are NOT supported because the don't support a[download] or dataURL frame locations.
## FAQ
---------
* `Can I tell when a download is done/canceled?` No.
* `How can I style the temporary download link?` Define CSS class styles for `.download-js-link`.
* `What's up with Safari?` I don't know either but pull requests that improve the situation are welcome.
* `Why is my binary file corrupted?` Likely: an incorrect MIME or using jQuery ajax, which has no bin support.
* `How big of files work?` Depends, try yourself: [File Echo Demo](http://pagedemos.com/gqs6hbmjcpem/)... I do a 1GB dl routinely on a thinkpad...
## Change Log (v4.1)
---------
* 2008 :: landed a FF+Chrome compat way of downloading strings to local un-named files, upgraded to use a hidden frame and optional mime
* 2012 :: added named files via a[download], msSaveBlob() for IE (10+) support, and window.URL support for larger+faster saves than dataURLs
* 2014 :: added dataURL and Blob Input, bind-toggle arity, and legacy dataURL fallback was improved with force-download mime and base64 support
* 2015 :: converted to amd/commonJS module with browser-friendly fallback
* 2015 :: 4.1 added direct URL downloading via a single URL argument.
* 2016 :: 4.2 added large dataURL support, a more semantic codebase, and hidden temp links
* 2017 :: added support for empty dataURLs
* 20XX :: ???? Considering Zip, Tar, and other multi-file outputs, Blob.prototype.download option, and more, stay tuned folks.