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Remove outdated section "Receiving binary data in older browsers" #36947

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Remove outdated section "Receiving binary data in older browsers" #36947

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33 changes: 6 additions & 27 deletions files/en-us/web/api/xmlhttprequest_api/sending_and_receiving_binary_data/index.md
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Expand Up @@ -6,6 +6,8 @@ page-type: guide

{{DefaultAPISidebar("XMLHttpRequest API")}}

## Receiving binary data

The `responseType` property of the XMLHttpRequest object can be set to change the expected response type from the server. Possible values are the empty string (default), `"arraybuffer"`, `"blob"`, `"document"`, `"json"`, and `"text"`. The `response` property will contain the entity body according to `responseType`, as an `ArrayBuffer`, `Blob`, `Document`, `JSON`, or string. This is `null` if the request is not complete or was not successful.

This example reads an image as a binary file and creates an 8-bit unsigned integer array from the raw bytes. Note that this will not decode the image and read the pixels. You will need a [png decoding library](https://github.com/foliojs/png.js) for that.
Expand Down Expand Up @@ -43,33 +45,6 @@ req.onload = (event) => {
req.send();
```

## Receiving binary data in older browsers

The `loadBinaryResource()` function shown below loads binary data from the specified URL, returning it to the caller.

```js
function loadBinaryResource(url) {
const req = new XMLHttpRequest();
req.open("GET", url, false);

// XHR binary charset opt by Marcus Granado 2006 [http://mgran.blogspot.com]
req.overrideMimeType("text/plain; charset=x-user-defined");
req.send(null);
return req.status === 200 ? req.responseText : "";
}
```

The magic happens in the `overrideMimeType` function, which forces the browser to treat it as plain text, using a user-defined character set. This tells the browser not to parse it, and to let the bytes pass through unprocessed.

```js
const fileStream = loadBinaryResource(url);
const lowestByte = fileStream.charCodeAt(x) & 0xff; // throw away high-order byte (f7)
```

The example above fetches the byte at offset `x` within the loaded binary data. The valid range for `x` is from 0 to `fileStream.length-1`.

See [downloading binary streams with XMLHttpRequest](https://web.archive.org/web/20071103070418/http://mgran.blogspot.com/2006/08/downloading-binary-streams-with.html) for a detailed explanation.

## Sending binary data

The `send` method of the XMLHttpRequest has been extended to enable easy transmission of binary data by accepting an [`ArrayBuffer`](/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer), {{domxref("Blob")}}, or {{domxref("File")}} object.
Expand Down Expand Up @@ -106,3 +81,7 @@ This is building a 512-byte array of 8-bit integers and sending it; you can use
## Submitting forms and uploading files

See [`FormData`](/en-US/docs/Web/API/FormData).

## See also

- [Downloading Binary Streams with Javascript XMLHttpRequest](https://web.archive.org/web/20071103070418/http://mgran.blogspot.com/2006/08/downloading-binary-streams-with.html) — explanation of receiving binary data in older browsers.