Find quotation marks with whitespace with RegEx

The best I can suggest is a regex that matches the string as a whole. For the problem here is that a local parsing can produce different results from a global parsing.

My attempt at a solution would be:

^[^"]*(?:"(?:[^"\s]|[^"\s][^"]*[^"\s])?"[^"]*)*$

Example in Rubular. Explanation:

• ^ - start of string
• [^"]* - followed by zero or more non-quotationable characters (text outside the quotation marks)
• (?:...)* - followed by zero or more of:
  • " - opens quotation marks
  • (?:...|...)? - with or without:
    • [^"\s] - a single character that is not quotation marks or spaces; or:
    • [^"\s] - a character that is not quotation marks or spaces, followed by
    • [^"]* - zero or more characters that are not double quotes, followed by
    • [^"\s] - a character that is not quotation marks or spaces, followed by
  • " - quoted quotes
  • [^"]* - zero or more non-quotationable characters (text outside the quotation marks)
• $ - end of string

Note that everything this regex talks about is whether the string is valid or invalid: it can not tell you what character the error is in.

Update: If what you want is a regex that casts strings with error - and tells you where the error is - this was the best I could do: / p>

^[^"]*(?:"(?:[^"\s]|[^"\s][^"]*[^"\s])?"[^"]*)*("(?:\s[^"]*|[^"]*\s)")[^"]*(?:"(?:[^"\s]|[^"\s][^"]*[^"\s])?"[^"]*)*$

Example in jsFiddle . This "monstrosity" boils down to:

^ regex_original ("(?:\s[^"]*|[^"]*\s)") regex_original $

That is, "marry something that is correct, followed by something that is incorrect, followed by something that is correct." It will detect one and only one error of that type - if the string has two or more errors, or if it has a quotation mark that opens but does not close, etc., regex will not be able to get it. >

I think with a little more effort you can improve this a bit, but we are getting to the point where regex is no longer the most suitable tool for the job ...

Here is a suggestion, which works in the text I've tried:

var texto = '" Jornal do Brasil". Paris é considerada a "Cidade Luz " Gosto das cores "azul" e "preto".';

var textoLimpo = texto.replace(/"([^"]*)"/g, function (match, r) {
    return '"' + r.replace(/^\s+|\s+$/g, '') + '"';
});
console.log(textoLimpo); // "Jornal do Brasil". Paris é considerada a "Cidade Luz" Gosto das cores "azul" e "preto".

Demo: link

In the background I divide the process into two parts. First isolating pieces starting and ending in " (quotation marks) and then cleaning one by one with r.replace(/^ | $/g, '') .

The first part /"([^"]*)"/g takes everything that is between two quotes, that is, using [^"]* I look for everything that does not have quotation marks, because I close the regex with " .

The second part uses the string start and end flag (resp: ^ and $ ) and using the | switch in the middle.

This expression will get anything inside quotation marks (including quotation marks). Ex: "This is not done"

"(.*?)(\w+)\b"