About the regular expression rollup of PHP

The following is a collection of some of the regular expressions used to organize, to facilitate future reference in the work, I hereby record.     can only enter a number: "^[0-9]*$"     can only enter n digits: "^\d{n}$"     can only enter at least n digits: "^\d{n,}$"     only can input m ~ n digits: "^\d{m,n}$"     can only enter numbers starting with 0 and 0: "^ (0[1-9][0-9]*) $"     can only enter positive real numbers with two decimal places: "^[0-9]+ (. [ 0-9]{2})? $     Only positive real numbers with 1~3 decimal places can be entered: ^[0-9]+ (. [ 0-9]{1,3})? $     can only enter a Non-zero positive integer: "^\+?" [1-9] [0-9]*$     can only enter a Non-zero negative integer: "^\-[1-9][0-9]*$"     can only enter characters of length 3: "^. {3}$     You can only enter a string of 26 English letters: "^[a-za-z]+$"     can only enter a string of 26 uppercase letters: "^[a-z]+$"     can only be entered by 26 Lowercase English character strings: "^[a-z]+$"     only strings consisting of numbers and 26 English letters can be entered: "^[a-za-z0-9]+$"     can only be entered by numbers, 26 English letters or underscore strings: "^\w+$"     Verifying user password: "^[a-za-z]\w{5,17}$" correct format bit: Start with a letter, length between 6~18, can only contain characters, numbers, and underscores     Verify that there are illegal characters ^ (?: [\u4e00-\u9fa5]*\w*\s*) +$     can only enter Chinese characters: "^[\u4e00-\u9fa5]{0,}$"     Verify Email Address: " ^\w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *$ "    validation InterneturL: "^http://" ([\w-]+\.) +[\w-]+ (/[\w-/?%&=]*)? $ "    China phone number verification     matching form such as: 0511-4405222 or 021-87888822 or 021-44055520-555 or (0511) 4405222     Regular expression ((d{3,4}) d{3,4}-)? d{7,8} (-d{3}) * "    China zip code validation   &N Bsp Matching forms such as: 215421     Regular expression "d{6}"     e-mail verification     match form such as: justali@justdn.com   Regular Expression w+ ([-+.] w+) *@w+ ([-.] w+) *.w+ ([-.] w+) * "    ID card verification     matching form such as: 15-bit or 18-bit ID card     regular expression" d{18}d{15} "    common digital validation   &NB Sp Regular expression     "D{n}" n for the specified length     "D{n,m}" N to m length range     Illegal character validation     match the character that excludes illegal characters Furu:     Regular Expression ^ (?: [\u4e00-\u9fa5]*\w*\s*) +$     Date validation     matching forms such as: 20030718,030718     Scope: 1900-- 2099     Regular expression ((({1} {1}) d{2}) [01]{1}d{1}[0-3]{1}d{1}     usages:     View Code Printing & nbsp