Regex Editor & Tester

This regex matches the root component of a Windows file path. It successfully identifies standard drive letters (e.g., `C:`), UNC paths (e.g., `\\Server\Share`), and extended-length paths (e.g., `\\?\C:` or `\\?\UNC\Server\Share`). It is highly useful for path manipulation, parsing directory structures, or validating user input to extract the base starting location of a file system hierarchy.