how to get proper binary string data with XHR without original mime type loss

Question

When I'm trying to just get data as binary string all 128+ characters have 65533 code. It can be walked around by overriding headers with text/plain ; charset=x-user-defined, but then I'm not able to read original mime type. Is there any way to extract original mime or get proper data without overriding headers?

Answer 1

65533 is U+FFFD, the Unicode replacement character. It seems that somewhere along the way (probably in the XHR), your data is being converted to Unicode incorrectly. Check the response to make sure it contains the proper data and has a Content-Type header specifying the right charset. If everything coming from the server checks out but you're still having trouble, you might try another well documented approach.