将UTF-8数据转换为正确的字符串格式

Question

If I receive a UTF-8 string via a socket (or for that matter via any external source) I would like to get it as a properly parsed string object. The following code shows what I mean

var str='21\r\nJust a demo string \xC3\xA4\xC3\xA8-should not be anymore parsed';

// Find CRLF
var i=str.indexOf('\r\n');

// Parse size up until CRLF
var x=parseInt(str.slice(0, i));

// Read size bytes
var s=str.substr(i+2, x)

console.log(s);

This code should print

Just a demo string äè

but as the UTF-8 data is not properly parsed it only parses it up to the first Unicode character

Just a demo string ä

Would anyone have an idea how to convert this properly?

Answer 1

It seems you could use this decodeURIComponent(escape(str)) :

var badstr='21\r\nJust a demo string \xC3\xA4\xC3\xA8-should not be anymore parsed';

var str=decodeURIComponent(escape(badstr));

// Find CRLF
var i=str.indexOf('\r\n');

// Parse size up until CRLF
var x=parseInt(str.slice(0, i));

// Read size bytes
var s=str.substr(i+2, x)

console.log(s);

BTW, this kind of issue occurs when you mix UTF-8 and other types of enconding. You should check that as well.

Answer 2

You should use utf8.js which is available on npm .

var utf8 = require('utf8');
var encoded = '21\r\nJust a demo string \xC3\xA4\xC3\xA8-foo bar baz';
var decoded = utf8.decode(encoded);
console.log(decoded);