Download Binary Files with Javascript
javascript
Solution
Have a look at the MDN article on XMLHttpRequest.
If you set the response of the XMLHttpRequest to ArrayBuffer you could do the following:
var xhr = new XMLHttpRequest();
xhr.open("GET", requestUrl);
xhr.responseType = "arraybuffer";
xhr.onload = function () {
if (this.status === 200) {
var blob = new Blob([xhr.response], {type: "application/pdf"});
var objectUrl = URL.createObjectURL(blob);
window.open(objectUrl);
}
};
xhr.send();
Option 2: You could use Blob as the response of the XMLHttpRequest. And then maybe save it in the FileSystem (FileSystem API)
It may look like:
var xhr = new XMLHttpRequest();
xhr.open("GET", requestUrl);
xhr.responseType = "blob";
xhr.onload = function () {
onDownloaded(this);
};
xhr.send();
Option 3: If you only want to download and "show" images you can easily do this like so:
var img = new Image();
// add the onload event before setting the src
img.onload = function() {
onImageDownloaded(img);
}
// start the download by setting the src property
img.src = requestUrl
Problem
I want to download binary files using Javascript. I have a REST service that returns the binary data and i want to know if its possible to show the binary file, whichever the file extension. This is my current code: ``` var xhr = new XMLHttpRequest; xhr.open("GET", requestUrl); xhr.addEventListener("load", function () { var ret = []; var len = this.responseText.length; var byte; for (var i = 0; i < len; i++) { byte = (this.responseText.charCodeAt(i) & 0xFF) >>> 0; ret.push(String.fromCharCode(byte)); } var data = ret.join(''); data = "data:application/pdf;base64," + btoa(data); window.open(data, '_blank', 'resizable, width=1020,height=600'); }, false); xhr.setRequestHeader("Authorization", "Bearer " + client.accessToken); xhr.overrideMimeType("octet-stream; charset=x-user-defined;"); xhr.send(null); ``` Thanks!