正则表达式需求：匹配指定字符串并过滤含无关行的文本

Let's work through this adjusted requirement together. First, let's recap what you need:

• Completely ignore lines with only irrelevant text (like "bla bla")
• Pull out all valid matching strings from lines that do contain targets:
  • Any string starting with thban (case-insensitive, with zero or more non-whitespace characters after it — this covers THBAN, THBANES900, THBANMP900, thbanes900, and all similar variants)
  • Any string starting with C3 followed by word characters (like C3950, C3850)
• Combine all extracted strings into one space-separated output

Adjusted Regular Expression #

To capture all your target strings while skipping irrelevant lines entirely, use this regex with global (g) and case-insensitive (i) modifiers:

\b(thban\S*|C3\w+)

How It Breaks Down #

Let's unpack the pattern to make it clear:

• \b: A word boundary, so we don't accidentally match partial words (like a thban substring inside a longer unrelated word)
• thban\S*: Matches thban (regardless of uppercase/lowercase) followed by 0 or more non-whitespace characters — this handles standalone THBAN as well as longer variants
• C3\w+: Matches C3 followed by 1 or more word characters (letters, numbers, underscores), which fits all your C3-prefixed examples
• |: Alternation, so the regex matches either the thban pattern or the C3 pattern

How to Use It #

1. Run a global, case-insensitive match of this regex against your entire file content
2. Collect all the matched results into a list
3. Join the list with spaces, and you'll get exactly the output you want: THBANES900 C3950 THBAN THBANES901 C3850 THBANMP900 thbanes900

For Find/Replace Tools (Text Editors, etc.) #

If you're using a tool that supports regex replace instead of direct matching:

• Find: [\s\S]*?(\b(thban\S*|C3\w+))|[\s\S]+
• Replace: $1
• Finally, trim any leading/trailing spaces and collapse multiple spaces into one (most editors have a built-in option for this, or you can do a quick follow-up replace of \s+ with )

This works by either capturing a valid target string and keeping it, or matching irrelevant content (including entire lines with no targets) and replacing it with nothing except the captured target (plus a space to keep results separated).

内容的提问来源于stack exchange，提问作者Marco