Unescaping multiple values in javascript

Question

Here is the code to escape special characters:

function escapeRegExp(string){
  return string.replace(/([.*+?^${}()|\[\]\/\\])/g, "\\$1");
}

How can I unescape the special characters to get the original strings?

I am getting confused with use of / and //.

Answer 1

That's pretty easy, you can use another function that removes the \\ characters.

// Use this to escape
function escapeRegExp(string){
    return string.replace(/([\.\*\+\?\^\$\{\}\(\)\|\[\]\/\\])/g, "\\$1");
}

// And this to unescape
function unescapeRegExp(string) {
    return string.replace(/\\([\.\*\+\?\^\$\{\}\(\)\|\[\]\/\\])/g, "$1")
}

// EXAMPLE:
escapeRegExp(".?[]");
> "\.\?\[\]"

unescapeRegExp("\.\?\[\]");
> ".?[]"

PS: I corrected your original function, the regular expression was wrong.

Answer 2

I guess, you've take this from MDN .

All you need to revert escaping is to remove every odd occurence of \\ character.

function unescapeRegExp(string) {
    return string.replace(/\\(.)/g, '$1');
}