Regular expressions of common use

Regular expressions for string processing, form verification, and other occasions, practical and efficient. Some commonly used expressions are collected here to prepare for a rainy-future.

Matching regular expressions for Chinese characters: [\U4E00-\U9FA5]
Commentary: Matching Chinese is really a headache, with this expression will be easy to do

match Two-byte character single-character expressions (including Chinese characters): [^\x00-\xff]
Commentary: can be used to compute the length of a string (a double-byte character length meter 2,ascii 1 characters)

a regular expression that matches a blank row : \n\s*\r
Commentary: can be used to delete blank lines

Regular expression:< matching HTML tags (\s*?) [^>]*>.*?</\1>|<.*? />
Commentary: The online version is too bad, the above can only match the part of the complex nested tags still powerless

a regular expression that matches the end-end whitespace character: ^\s*|\s*$
Commentary: A useful expression that can be used to delete white-space characters (including spaces, tabs, page breaks, and so on) at the end of a line at the beginning

Regular expression matching an email address : \w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *
Commentary: Form validation is useful

regular expressions that match URL URLs : [a-za-z]+://[^\s]*
Commentary: Online circulation of the version of the function is very limited, which can meet the basic requirements

Match account number is legal (beginning of letter, allow 5-16 bytes, allow alphanumeric underline): ^[a-za-z][a-za-z0-9_]{4,15}$
Commentary: Form validation is useful

Match Domestic phone number : \d{3}-\d{8}|\d{4}-\d{7}
Commentary: Match form such as 0511-4405222 or 021-87888822

matching Tencent QQ number : [1-9][0-9]{4,}
Commentary: Tencent QQ number starting from 10000

match China ZIP code : [1-9]\d{5} (?! \d)
Commentary: China postal code is 6 digits

Matching ID : \d{15}|\d{18}
Commentary: China's ID card is 15-or 18-digit

match an IP address regular expression : \d+\.\d+\.\d+\.\d+
Commentary: Useful when extracting IP addresses

Match a specific number:
^[1-9]\d*$//Matching positive integer
^-[1-9]\d*$//matching negative integers
^-? [1-9]\d*$//matching integer
^[1-9]\d*|0$//matching nonnegative integer (positive integer + 0)
^-[1-9]\d*|0$//matching non positive integer (negative integer + 0)
^[1-9]\d*\.\d*|0\.\d*[1-9]\d*$//matching positive floating-point numbers
^-([1-9]\d*\.\d*|0\.\d*[1-9]\d*) $//matching negative floating-point number
^-? ([1-9]\d*\.\d*|0\.\d*[1-9]\d*|0?\.0+|0) $//matching floating-point number
^[1-9]\d*\.\d*|0\.\d*[1-9]\d*|0?\.0+|0$//matching nonnegative floating-point number (positive floating-point number + 0)
^ (-([1-9]\d*\.\d*|0\.\d*[1-9]\d*)) |0?\.0+|0$//matching non-positive floating-point numbers (negative floating-point number + 0)
Commentary: useful when dealing with large amounts of data, pay attention to corrections when applied

Match a specific string:
^[a-za-z]+$//Match a 26-letter string
^[a-z]+$//Match a string of 26-letter caps
^[a-z]+$//Match a string of 26-Letter lowercase characters
^[a-za-z0-9]+$//matches a string of numbers and 26 English letters
^\w+$//matches a string of numbers, 26 English letters, or underscores
Commentary: Some of the most basic and commonly used expressions