如何编写匹配引号内非空非空白字符串的正则？现有正则存空匹配问题

Hey there! Let's tackle your regex problem. Your current pattern var regex = new Regex("\"([^\"]+)\"") has a small gap: while it won't match empty quotes ("") thanks to the + quantifier, it will match quotes filled only with whitespace (like " " or "\\t\\n") because whitespace characters aren't excluded by [^"].

The Solution: Regex That Ensures At Least One Non-Whitespace Character #

We need to modify the regex to guarantee that the content inside the quotes has at least one non-whitespace character. Here's a robust, easy-to-understand implementation:

var regex = new Regex(@"\""(?=[^\"]*\S)[^\"]*\""");

Breakdown of the Pattern #

Let's break down each part to see how it works:

• \"" : Matches the opening double quote (we use C#'s verbatim string @ to avoid messy escape character headaches)
• (?=[^\"]*\S) : A positive lookahead that checks if there's at least one non-whitespace character (\S) somewhere inside the quotes before the closing quote. [^\"]* matches any number of non-quote characters leading up to that non-whitespace.
• [^\"]* : Matches all characters inside the quotes (including whitespace, but only if there's at least one non-whitespace present, thanks to the lookahead)
• \"" : Matches the closing double quote

What It Matches & Doesn't Match #

• ✅ Matches: "hello world", " test ", "a\tb\nc", "mix of spaces and text"
• ❌ Doesn't Match: "", " ", "\\t\\n", " "

Handling Edge Cases (Optional) #

If your use case includes escaped quotes inside the string (e.g., "He said \"Hello!\""), you'll need to adjust the regex to ignore escaped quotes. Here's the modified version:

var regex = new Regex(@"\""(?=(?:\\.|[^\"\\])*\S)(?:\\.|[^\"\\])*\""");

This version uses (?:\\.|[^\"\\]) to match either an escaped character (like \") or any non-quote, non-backslash character, ensuring escaped quotes don't break the match.

内容的提问来源于stack exchange，提问作者Kseniya Yudina