使用正则表达式捕获`\\“`并拆分成数组

Question

I have come across something that I haven't seen before and google is no use because it keeps removing \\" from my search.

First of all, what does \\" mean? I am accessing an API and for one of the key's values it is a string of tags, but then if one of the tags has two words it uses \\" to show that the tag is two words. Example below

"foo bar baz \\"taz foo\\" goo too loo"

I am trying to split those up into an array like so ["foo", "bar", "baz", "taz foo", "goo", "too", "loo"]

However I am having one hell of a time figuring out how to capture the \\" and making it so I can split them to an array like above.

Answer 1

Use String.prototype. replace() for fun and profit:

var s = "foo bar baz \"taz foo\" goo too loo";

var arr = [];
s.replace(/[^\s"]+|"[^"]*"/g, function($1) {
  arr.push($1.replace(/"/g,''));
});

console.log(arr); // ["foo", "bar", "baz", "taz foo", "goo", "too", "loo"]

---

Create an empty array arr to push matches into
Use replace to collect $1 matches: anything that is
[^\\s"]+ not a whitespace or doubleQuote (one or infinite times)
| or
"[^"]*" anything between " " that is not a quote [^"] (zero or infinite times * )

Answer 2

\\" means to escape the double quote character. It's called an escape character .

If you want to use a double inside a string that is double quoted, you will have to use the escape character.

Say for example you want to store a string abcd"xyz"abcd

console.log("abcd"xyz"abcd");

will give you an error because double quotes before xyz mark the end of string and quote after xyz mark the beginning of new string, hence an error occurs because of improper syntax.

Therefore to have double quotes inside a string you will have to

either escape the double quotes using \\"

console.log("abcd\"xyz\"abcd");

or put double quotes inside a single quoted string

console.log('abcd"xyz"abcd');

As for your splitting question, you can split on a regex to get that array like this:

> "foo bar baz \"taz foo\" goo too loo".match(/\w+|(?:")[^"]*?(?:")/g);

["foo", "bar", "baz", ""taz foo"", "goo", "too", "loo"]

and then you can iterate over the array and remove double quotes like this:

> '"abcd xyz"'.replace(/"/g, '');
"abcd xyz"

Combined code:

> arr="foo bar baz \"taz foo\" goo too loo".match(/\w+|"[^"]*?(?=")/g);
["foo", "bar", "baz", ""taz foo", "goo", "too", "loo"]
> for(var i=0;i<arr.length;i++){arr[i]=arr[i].replace(/"/g, '');}
> console.log(arr);
["foo", "bar", "baz", "taz foo", "goo", "too", "loo"]