UTF-16 in nodejs

Question

I have a file.txt and content of it is:

\u0048\u0065\u006c\u006c\u006f\u0020\u0057\u006f\u0072\u006c\u0064\u0021

It is 'Hello World!' in UTF-16.

If my code is:

let data = '\u0048\u0065\u006c\u006c\u006f\u0020\u0057\u006f\u0072\u006c\u0064\u0021';
console.log(data);

It is print out: 'Hello World!'

But If I use readFileSync() and console.log(), it isn't print out 'Hello World!':

let data = fs.readFileSync('file.txt',{encoding:'utf8', flag:'r'});
console.log(data);

Why?

Example:

Example

I mean: '\u0048\u0065\u006c\u006c\u006f\u0020\u0057\u006f\u0072\u006c\u0064\u0021' in normal text file — stupidquestion
– stupidquestion, Commented Jun 21, 2021 at 13:47

Quentin · Accepted Answer · 2021-06-21 13:23:18Z

4

In the source code of a JavaScript string literal, \u followed by four characters represents a position in the Basic Multilingual Plane.

The same numbers, expressed in bytes, mean the same thing in various Unicode encodings.

Your text file doesn't contain bytes that represent those characters.

It contains bytes which represent the \ character, the u character, etc.

answered Jun 21, 2021 at 13:23

Quentin

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2 Comments

So, what should i do to convert data read from file to utf8?

I'd store the data as text (as opposed to JS source code) in the first place.