useful-regexes

A rag-tag collection of Regexes, hopefully worth saving for future use

CONTRIBUTIONS WELCOME

Validation

• Email

  • /^[\w]+[\.\w]*[\w]+@\w+\.{1}[\w]+\.?[\w]+$/

• Filename

  • Based on characters restricted by windows
  • /^(?<name>[^\\\/:*?"<>|\s]+)\.(?<type>[^\\\/:*?"<>|\s]+)$/

Parsing

• URL

  • /(?:(?<protocol>https?):\/\/)?(?<host>(?:(?:[\w\-\~]+\.)+[\w]+)|(?:localhost)){1}(?::(?<port>\d+))?(?<path>\/[\w\-\~\.\/]+)?(?:#(?<fragment>[\w\-\~]+))?(?:\?(?<query>[\w\-\~\=\&]+))?/

• Flexible CLI ARGS

  • Matches cli flags & corresponding arguments, flexible to allow use of equals sign and also allow spaces in arg if enclosed in matching brackets
  • /-{1,2}(?<flag>\w+)(?:(?:(?=\s*=)\s*=\s*|\s+)(?<br>['"])?(?<arg>(?:(?!\k<br>)(?!-))(?:(?!\k<br>)(?(<br>)[^\n\r]|[^\s]))*)(?(<br>)\k<br>))?/

Misc

• Find Images with empty or missing alt attributes
  • /<img (?:alt="" *)*(?:(?!alt)[-\d\w]+="[^"]*" *)*(?:alt="" *)*(?:(?!alt)[-\d\w]+="[^"]*" *)*(?:alt="" *)*\/?>/