The most commonly used PHP regular expression collection

Regular expression regular expressions are used for string processing, form verification, and so on, and are practical and efficient. This article collects some common expressions:

Matching regular expressions for Chinese characters: [\U4E00-\U9FA5]

Commentary: Matching Chinese is really a headache, with this expression will be easy to do

Match Double-byte characters (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

Matching IP address: \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 string of 26 English letters

^[a-z]+$//Match a string of 26 uppercase letters

^[a-z]+$//Match string consisting of 26 lowercase letters

^[a-za-z0-9]+$//Match a string of numbers and 26 English letters

^\w+$//Match A string of numbers, 26 English letters, or underscores