ActionScript ByteArray manipulation

I开发者_Go百科 have some binary data and I can't store it in a string, as such I'm using a ByteArray. The problem is that I need some functionality that comes with strings, to be specific I need the charAt, substr, indexOf and substring methods.

These would be fairly easy to implement. I can post the code if wanted. Is the data string-like? Or does it need to be treated as arbitrary binary? In either case, how wide are characters (e.g. 8-bit, 16-bit)?

public static function charAt(bytes:ByteArray, index:int):String {
    if (bytes.length <= index) return null; 
    return String.fromCharCode(bytes[index]); 
} 

public static function substr(bytes:ByteArray, start:int, length:int=0):String { 
    var res:ByteArray = bytes.readBytes(bytes, start, length); 
    return res.toString(); 
} 

public static function substring(bytes:ByteArray, start:int, end:int=0):String { 
    return substr(bytes, start, end-start); 
}

public static function indexOf(bytes:ByteArray, str:String):int { 
    for (var i:int=0; i<bytes.length; i++) { 
        var strPos:int = 0; 
        while (String.fromCharCode(bytes[i+strPos]) == str.charAt(strPos)) { 
            strPos++; 
            if (strPos == str.length) return i; 
        } 
    } 
    return -1; 
}