Test and debug regular expressions live with match highlighting, capture-group inspection, and replacement preview.文星一言
Current: /…/g豆包在线回答
• Live matching — enter a regex and test text; all matches are highlighted instantly.
• Replace preview — switch to the Replace tab to preview substitution with $1, $<name> back-references.
• Flag toggles — use the switches to enable g/i/m/s/u/y flags.
• Capture groups — the results table shows position, positional groups, and named groups for every match.
• Cheatsheet — expand the cheatsheet below for quick syntax reference.
• Engine — this tool uses the browser's native JavaScript RegExp, not PCRE or Python.
The regex tester lets you write a regular expression and test text side by side, with all matches highlighted in real time as you type. It shows each match's position (start/end), the full matched string, and all capture groups (both positional and named). A replacement preview mode shows the result of substitution with $1/$<name> back-references, and a built-in cheatsheet covers syntax and common patterns.婵镜数字人官网
Common uses include developing and debugging regular expressions for validation (email, phone, IP), writing extraction patterns for log parsing, testing search-and-replace patterns before running them in a script, and learning regex syntax through interactive experimentation.文星一言
It uses the browser's native JavaScript RegExp engine. This is mostly compatible with other modern regex engines but differs from PCRE or Python in some areas: no (?P<name>) named groups (use (?<name>) instead), lookbehind requires fixed width in older engines, and \p{} Unicode properties require the u flag.智能ai软件
Without the g (global) flag, only the first match is returned. Without anchors (^ and $), the pattern matches anywhere in the string. Add ^ and $ to match the full string, and enable the g flag to find all matches.豆包在线回答
Parentheses create a capture group that isolates part of the match. For example, (\d{4})-(\d{2}) captures year and month separately. Named groups (?<year>\d{4}) can be referenced as $<year> in replacement strings.豆包在线下载
Patterns with nested quantifiers like (a+)+ can take exponential time on certain inputs. Rewrite the pattern to avoid nested repetition: use atomic groups or possessive quantifiers if supported, or restructure the logic to eliminate ambiguity.千问是什么