正则表达式优化：提取INPUTBOX中带可选引号的string1与string2

Alright, let's tweak that regex to cover all your requirements properly. Here's a refined solution that addresses the newline issue, supports multiple <INPUTBOX> instances, and enforces the colon-only-when-string2-exists rule:

/<INPUTBOX:(?|"[\n]?(.*?)"|([^:>]+))(?:\s*:\s*(?|"([^"]*)"|([^>]*)))?>/g

Breakdown of the Regex #

Let's walk through each part to understand how it fixes your original issues:

• <INPUTBOX:: Matches the fixed opening of your input box tag.
• (?|"[\n]?(.*?)"|([^:>]+)): A branch reset group that ensures string1 lands in a consistent capture position, regardless of quotes:
  • First branch ("[\n]?(.*?)"): Handles quoted string1 cases. The [\n]? skips any optional newline right after the opening quote, so it doesn't get included in the captured string1 (exactly what you asked for).
  • Second branch (([^:>]+)): Handles unquoted string1 cases, matching all characters until either a colon (if string2 exists) or the closing >.
• (?:\s*:\s*(?|"([^"]*)"|([^>]*)))?: An optional non-capturing group for string2, which only triggers if a colon is present:
  • \s*:\s*: Matches the colon, allowing optional whitespace (spaces, tabs, newlines) around it for flexibility.
  • Inner branch reset group ((?|"([^"]*)"|([^>]*))): Captures string2 in a consistent position, whether it's quoted (matches until the closing quote) or unquoted (matches until the closing >).
• >: Matches the fixed closing of the input box tag.
• /g: Global flag to match all <INPUTBOX> instances in a string, not just the first one.

Example Usage (JavaScript) #

Here's how you can use this regex to extract values in practice:

const inputStr = `
  Sample text with multiple inputs:
  <INPUTBOX:"\nHello World">
  <INPUTBOX:foo:"bar baz">
  <INPUTBOX:no-quotes:1234>
`;

const regex = /<INPUTBOX:(?|"[\n]?(.*?)"|([^:>]+))(?:\s*:\s*(?|"([^"]*)"|([^>]*)))?>/g;
let match;

while ((match = regex.exec(inputStr)) !== null) {
  const string1 = match[1] || match[2]; // Grab string1 from whichever branch captured it
  const string2 = match[3] || match[4]; // Grab string2 if it exists
  console.log(`String 1: "${string1}", String 2: ${string2 ? `"${string2}"` : "undefined"}`);
}

Output:

String 1: "Hello World", String 2: undefined
String 1: "foo", String 2: "bar baz"
String 1: "no-quotes", String 2: "1234"

Notes #

• This regex assumes quotes are unescaped (no \" inside quoted values). If you need to support escaped quotes, we'd need to adjust the quoted branches to handle that, but it wasn't mentioned in your requirements.
• The regex is case-sensitive as written. If you need case-insensitive matching for <INPUTBOX>, add the i flag (e.g., /.../gi).

内容的提问来源于stack exchange，提问作者Michael T