Javascript Regex Quote

I'm having trouble getting this Javascript Regular Expression to work. What i want is to find a character that starts with @' has any characters in the middle and ends with '. I wi

Solution 1:

Try this regular expression:

/@(["'])[^]*?\1/g

An explanation:

• @(["']) matches either @" or @'
• [^]*? matches any arbitrary character ([^] contains all characters in opposite to . that doesn’t contain line-breaks), but in a non-greedy manner
• \1 matches the same character as matches with (["'])

Using the literal RegExp syntax /…/ is more convenient. Note that this doesn’t escape sequences like \" into account.

Solution 2:

The regex would be: var regex = /@"[^"]*"/g;

Solution 3:

Gumbo's regexp is very nice and all, however it fails to detect escaped quotes (e.g. \", \\\", etc.). A regexp that solves this is as follows:

/@(["'])[^]*?[^\\](?:\\\\)*\1|@""|@''/g

An explanation (continuing from Gumbo's explanation):

• [^\\] matches the nearest character preccedding the ending quote that is not a backslash (to anchor the back-slash count check).
• (?:\\\\)* matches only if the number of backslashes is a multiple of 2 (including zero) so that escaped backslashes are not counted.
• |@"" checks to see if there is an empty double quote because [^\\] requires at least one character present in the string for it to work.
• |@'' checks to see if there is an empty single quote.