[SOLVED] Reading any file type and encoding it to Base64

[PranKe01]

Hi guys,

I spent days on this problem and no one seems to have a solution.
I want to communicate with a WebService via SOAP. This WebService got a function to send and receive files, which are encoded in Base64. I found a lot of implementations of the Base64 encoder/decoder - for example this one: http://www.webtoolkit.info/javascript-base64.html
Adobe Air uses WebKit so there are also the functions atob and btoa available.

The Base64 thing should work. Now the reading of the files... I want to read any type of file - I think this function should work:

    this.readFile = function(inputfile){
        var file = new air.File(inputfile);
        var bytes = new air.ByteArray();
        if (file.exists) {
            var stream = new air.FileStream();
            stream.open(file, air.FileMode.READ);
            bytes.endian = air.Endian.LITTLE_ENDIAN;
            stream.readBytes(bytes, 0, file.size);
            stream.close();
        }
        
        return bytes;
    };

I create the Base64 string like this:

var binary = c_FileManager.readFile('Stunden.xlsx');
air.trace(encodeBase64(binary.toString()));

The created string is not correct. It almost looks right, but some Bytes seem to be interpreted not correct.

This is how it should look:

...NtWUQbCGicTcUg7osIbOa0sctUvM9eevciQlJWq8JZSMUOUIxH11fJbOcBI15tMRU5kX+QErMcSoWx82D5y8KFUhE...

This is what I get:

...NtWUQbCGicTcUg7osIbDHLVLzPXnr3IkJSVqvCWUjFDlCMR9dXyWznASNebTEVOZF/kBKzHEqFsfNg+cuFUhE...

I think the problem is how I read the files or how I use the Base64 encoder with the ByteArray type.

I don't know how I can solve the problem

[PranKe01]

I think the problem is when I cponvert the ByteArray to the Base64 string. When I read in a file and write it back, it works. But when I read a file and convert it to Base64 some pieces of the string are wrong. Maybe some bytes are not supported to convert?
Any hints?

[PranKe01]

Hi guys,

I fixed the problem Here is the code I use to convert ByteArrays to Base64 and Base64 to ByteArrays:

var byteArrayToBase64 = function(byteArr){
    var base64s = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    var encOut = "";
    var bits;
    var i = 0;
    
    while(byteArr.length >= i+3){
        bits = (byteArr[i++] & 0xff) << 16 | (byteArr[i++] & 0xff) << 8 | byteArr[i++] & 0xff;
        encOut += base64s.charAt((bits & 0x00fc0000) >> 18) + base64s.charAt((bits & 0x0003f000) >> 12) + base64s.charAt((bits & 0x00000fc0) >> 6) + base64s.charAt((bits & 0x0000003f));
    }
    if(byteArr.length-i > 0 && byteArr.length-i < 3){
        var dual = Boolean(byteArr.length - i - 1);
        bits = ((byteArr[i++] & 0xff) << 16) | (dual ? (byteArr[i] & 0xff) << 8 : 0);
        encOut += base64s.charAt((bits & 0x00fc0000) >> 18) + base64s.charAt((bits & 0x0003f000) >> 12) + (dual ? base64s.charAt((bits & 0x00000fc0) >> 6) : '=') + '=';
    }
    
    return encOut;
};
    
var base64ToByteArray = function(encStr){
    var base64s = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    var decOut = new air.ByteArray();  
    var bits;
    
    for(var i = 0, j = 0; i<encStr.length; i += 4, j += 3){
        bits = (base64s.indexOf(encStr.charAt(i)) & 0xff) <<18 | (base64s.indexOf(encStr.charAt(i +1)) & 0xff) <<12 | (base64s.indexOf(encStr.charAt(i +2)) & 0xff) << 6 | base64s.indexOf(encStr.charAt(i +3)) & 0xff;
        decOut[j+0] = ((bits & 0xff0000) >> 16);
        if(i+4 != encStr.length || encStr.charCodeAt(encStr.length - 2) != 61){
            decOut[j+1] = ((bits & 0xff00) >> 8);
        }
        if(i+4 != encStr.length || encStr.charCodeAt(encStr.length - 1) != 61){
            decOut[j+2] = (bits & 0xff);
        }
    }
    
    return decOut;
};

It took me some days, to find the problem - I hope I can help somebody with this

[piroman]

LOOOOOOOL what a mess

why dont u just use following functions
atob : base64decode
btoa : base64encode

hope it helps

[PranKe01]

No it doesn't. Thanks for your answer - next time please read the whole thread insteas of only the last one.
The WebKit functions does NOT support ByteArrays! My function does only work with them.

[nrako]

You saved my day thank you so much!

[dolittle]

@PranKe01

I'm using your code and it works great but I saw weird result recently.
I'm trying to base64 encode the array

[131,104,5]

which should result with:

"g2gF"

Sometimes I'm getting:

"g2gf"

lower f instead of capital F.

I'm still not sure on what platform, OS, browser I'm getting the wrong lower f.

Any idea how to fix it?