Regular expression to replace (") with (\")?

Question

Why does the following not work:

      String test = "hello\"world".replaceAll("\"", "\\\"");
      System.out.println(test);

What I'm trying to do is replace any occurrence of " with \".

So I want to get as output:

hello\"world

You're escaping the ". Try .replaceAll("\\"", "\\\"");

SomeKittens
– SomeKittens

2012-07-10 16:34:28 +00:00
Commented Jul 10, 2012 at 16:34 — SomeKittens
– SomeKittens, Commented Jul 10, 2012 at 16:34
This does not even compile...

Sweety
– Sweety

2012-07-10 16:36:31 +00:00
Commented Jul 10, 2012 at 16:36 — Sweety
– Sweety, Commented Jul 10, 2012 at 16:36
Why do you think you need to do this?

user207421
– user207421

2012-07-11 01:50:14 +00:00
Commented Jul 11, 2012 at 1:50 — user207421
– user207421, Commented Jul 11, 2012 at 1:50

Mike Samuel · Accepted Answer · 2012-07-10 16:37:16Z

6

Regular expressions are overkill for this.

myString.replace("\"", "\\\"")

should do just fine and is more readable to someone familiar with the core libraries.

The replace method just replaces one substring with another.

Replaces each substring of this string that matches the literal target sequence with the specified literal replacement sequence. The replacement proceeds from the beginning of the string to the end, for example, replacing "aa" with "b" in the string "aaa" will result in "ba" rather than "ab".

answered Jul 10, 2012 at 16:37

Mike Samuel

121k30 gold badges230 silver badges255 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

cklab Over a year ago

I think this is the best solution.

Sweety Over a year ago

Yes, I agree! An obvious, but probably easily overlooked solution. thanks.

cklab · Accepted Answer · 2012-07-10 16:37:52Z

0

You need to two more \\ to escape the escape character, for a total of 5 \s.

\\ - escape the escape character

\\ - to display the character

\ - to escape the quote.

Try:

String test = "hello\"world".replaceAll("\"", "\\\\\"");

answered Jul 10, 2012 at 16:37

cklab

3,77122 silver badges29 bronze badges

Comments

bluish · Accepted Answer · 2012-07-11 15:24:39Z

0

String test = "hello\"world".replaceAll("\"", "\\\\\"");
System.out.println(test);

edited Jul 11, 2012 at 15:24

bluish

27.5k28 gold badges126 silver badges185 bronze badges

answered Jul 10, 2012 at 16:37

Jon Lin

144k29 gold badges226 silver badges224 bronze badges

Collectives™ on Stack Overflow

Regular expression to replace (") with (\")?

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related