Flutter JSON encode raw string

Issue

So I have this json data that contains strings \r (carriage return) and \n (new line) - It's from Firebase. The problem is when I encode the data using json.encode it add an escaping character. So \r becomes \\r. I'm sending that data to an another server. json.encode works as expected if I do json.encode({'hello': 'world\r\n'}) but it adds \ when I used it on my other string.

Am I missing something? Is there some type of encoding to prevent it from adding \?

Solution

It seems that the data you received does not contain CR and LF characters but contains their escape sequences (\ followed by r and \ followed by n). Therefore when you encode that to JSON, it will be escaped again.

You could do:

data = data.replaceAll('\\r', '\r').replaceAll('\\n', '\n');

which probably would work most of the time, but it would have the corner case of undesirably replacing occurrences that were explicitly intended to be escaped. (That is, a string '\\n' would be transformed to a sequence \, LF.)

Since the data is already escaped, you probably could unescape it with json.decode. Of course, decoding the data as JSON just to re-encode it to JSON seems a little silly, so if it's already properly encoded JSON, you ideally should pass it through it unchanged.

Answered By - jamesdlin