How to replace Backslash '\' with double Backslash in Dart?

Question

How to replace a Single Backslash '\' in a String with double Backslash '\' ?

I tried this, but its not working.

main(){
String string = "back\slash back\slash back\slash back\slash";
String replaced = string.replaceAll(RegExp(r'\\'), '\\\\');
print(replaced);
}

Do you get an error? What output do you get? – Günter Zöchbauer Feb 15 '19 at 16:56 — Günter Zöchbauer, Feb 15 '19 at 16:56
No error , just I was unable to accomplish what I needed. – Shahzad Akram Feb 15 '19 at 17:31 — Shahzad Akram, Feb 15 '19 at 17:31

Günter Zöchbauer · Accepted Answer · 2019-02-15T17:45:42.067

17

The problem is that the string string does not contain any \

It would either need to be

String string = r"back\slash back\slash back\slash back\slash";

or

String string = "back\\slash back\\slash back\\slash back\\slash";

In your example there also is no need for RegExp. Just

String replaced = string.replaceAll(r'\', r'\\');

would do as well.

edited Feb 15 '19 at 17:45

answered Feb 15 '19 at 16:59

This has to do with how Dart handles raw strings, for further explanation see [How to Create A Raw String In Dart](https://www.educative.io/edpresso/how-to-create-a-raw-string-in-dart) – CoderBlue Sep 12 '21 at 00:38

1 Answers1