Base64编码btoa

Question

I am encoding some text on my frontend part using btoa function:

const encodedText = btoa(searchText);

This seems to work totally fine and decoding goes like this on backend part:

byte[] decodedBytes = Base64.getDecoder().decode(searchedText);
String decodedString = new String(decodedBytes, Charset.defaultCharset());

Which also works fine. However, this seems to fail when using ü letter. My program encodes it as A==, and as far as I know, it should be w7w=

I am not sure what I did wrong.

Answer 1

You could use

const encodedText = btoa(unescape(encodeURIComponent(searchText)));

instead to encode unicode characters first.

See Unicode strings and The "Unicode Problem" for further reading.

 console.log(btoa('ü')); console.log(btoa(unescape(encodeURIComponent('ü'))));