Compression of strings using using blobs in JavaScript.

compressor.js

var zip = new JSZip();
function en(text, callback){
        var thefile = zip.file("file.zip", text);
        var reader = new FileReader();
        reader.onload=callback // e.target.result
        thefile.generateAsync({ type: "blob" }).then(function (content) {
		reader.readAsDataURL(content);
	});
}

function dataURItoBlob(dataURI) {
    // convert base64 to raw binary data held in a string
    // doesn't handle URLEncoded DataURIs - see SO answer #6850276 for code that does this
    var byteString = atob(dataURI.split(',')[1]);

    // separate out the mime component
    var mimeString = dataURI.split(',')[0].split(':')[1].split(';')[0];

    // write the bytes of the string to an ArrayBuffer
    var ab = new ArrayBuffer(byteString.length);
    var ia = new Uint8Array(ab);
    for (var i = 0; i < byteString.length; i++) {
        ia[i] = byteString.charCodeAt(i);
    }

    //Old Code
    //write the ArrayBuffer to a blob, and you're done
    //var bb = new BlobBuilder();
    //bb.append(ab);
    //return bb.getBlob(mimeString);

    //New Code
    return new Blob([ab], {type: mimeString});


}

function de(text, callback){
        zip.loadAsync(dataURItoBlob(text), {type: "blob"}).then(function (zip) {
                Object.keys(zip.files).forEach(function (filename) {
                        zip.files[filename].async('string').then(function (fileData) {
                                callback(fileData);
                        })
                })
        })
}