Javascript正则表达式获取不在单引号或双引号中的字符串列表

Question

Guy I have a list of string.

Select 
id AS "cusId ",
name as 'cusName', gendar as ' Gendar.',
isPaid as " is'Paid ", total, remarks FROM

I need a regex that returns:

Select
id
name
gendar
isPaid
total
remarks
FROM

And also ignore comma and 'AS' keyword.

So far from PHP I can use preg_match_all('/(?<![\\S"])([^"\\'\\s]+)(?![\\S"])/') and filter all query keywords later on, but came to JavaScript there is no lookbehind in regex.

Answer 1

DISCLAIMER: The solution below is by no means a generic solution for parsing arbitrary SQL queries. To parse arbitrary SQL queries, you need to build or use an existing one. See also How to parse / tokenize an SQL statement in Node.js .

So, taking into account your specific input strings , you can use a regex that will match what you do not need, and then will capture what you need:

/"[^"]*"|'[^']*'|\s+AS\s+|\s*((?:(?!\sAS\s)[^,\s])+)/gi

See the regex demo

Explanation :

• "[^"]*" - match a double-quoted substring that has no " inside (replace with "[^"\\\\]*(?:\\\\.[^"\\\\]*)*" if you need to support escaped " inside)
• | - or
• '[^']*' - match single-quoted substring having no ' inside (replace with '[^'\\\\]*(?:\\\\.[^'\\\\]*)*' if you need to support escaped ' inside)
• | - or
• \\s+AS\\s+ - "AS" word inside 1+ whitespaces
• | - or
• \\s* - 0+ whitespaces
• ((?:(?!\\sAS\\s)[^,\\s])+) - Group 1 capturing one or more symbols other than , and whitespace (see [^,\\s])+ ) that are not starting a sequence of a whitespace + AS + whitespace. It matches any text that is not space + AS + space .

JS demo:

 var re = /"[^"]*"|'[^']*'|\\s+AS\\s+|\\s*((?:(?!\\sAS\\s)[^,\\s])+)/gi; var str = 'Select id AS "cusId ", name as \\'cusName\\', gendar as \\' Gendar.\\', isPaid as " is\\'Paid " total , datetime FROM'; var res = []; while ((m = re.exec(str)) !== null) { if (m[1]) { res.push(m[1]); // Add the Capture group 1 to the resulting array } } document.body.innerHTML = "<pre>" + JSON.stringify(res, 0, 4) + "</pre>";