Regular expressions of numbers, 26 English letters, underscores, or Chinese characters __ regular expressions

Reprint Address: https://blog.csdn.net/qiaoxinde/article/details/49783491 Regular expressions of numbers, 26 English letters, underscores, or Chinese charactersBlog Category: JS regular expression

HTML code    1. A string of numbers, 26 English letters, or underscores:       ^[0-9a-zA-Z_]{1,}$   2. nonnegative integers (positive integers  + 0 ):       ^/d+$   3.  positive integers:       ^[0-9]*[1-9][0-9]*$   4. Non-positive integers (negative integer  + 0):        ^ ((-/d+) | ( 0+) $   5.  negative integer  :       ^-[0-9]*[1-9][0-9]*$   6 integer:            ^-?/d+$   7. Non-negative floating-point number (positive floating-point number  + 0):        ^/d+ (/./d+)?$   8. Positive float  :        ^ ([0-9]+/. [0-9]*[1-9][0-9]*) | ([0-9]*[1-9][0-9]*/. [0-9]+) | ([0-9]*[1-9][0-9]*)] $   9.  non-positive floating-point numbers (negative floating-point number  + 0):       ^ (-/d+ (/./d+)?) | (0+ (/.0+)) $   10. Negative floating-point number  :       ^ (-([0-9]+/.[ 0-9]*[1-9][0-9]*) | ([0-9]*[1-9][0-9]*/. [0-9]+)| ([0-9]*[1-9][0-9]*))] $   11.  floating-point number  :       ^ (-?/d+) (/./d+)?$   12. A string consisting of 26 English letters  :           ^[A-Za-z]+$   13.   A string of 26 uppercase letters  :       ^[A-Z]+$   14. A string consisting of 26 lowercase letters  :       ^[a-z]+$   15.  A string of numbers and 26 English letters  :       ^[A-Za-z0-9]+$   16. A string of numbers, 26 English letters, or underscores  :            ^/w+$   17.email Address  :       ^[/ w-]+ (/.[ /w-]+) *@[/w-]+ (/.[ /w-]+) +$   18.url:           ^[a-za-z]+://(/w+ (-/w+) *)(/. (/w+ (-/w+) *)) * (/?/s*)?$   19.  year-month-day:       /^ (D{2}|d{4})-((0 ([1-9]{1})) | ( 1[1|2])-(([0-2] ([1-9]{1})) | ( 3[0|1]) $/   20. Month/day/year: &NBsp;      /^ ((0 ([1-9]{1})) | ( 1[1|2]))/(([0-2] ([1-9]{1})) | ( 3[0|1])/(d{2}|d{4}) $/   21.emil:       ^ ([w.] +) @ ([[0-9]{1,3}. [0-9] {1,3}. [0-9] {1,3}.) | (([w-]+.) +)) ([a-za-z]{2,4}| [0-9] {1,3}) (]?) $   22.  Phone number:        (d+-)? (d{4}-?d{7}|d{3}-?d{8}|^d{7,8}) (-d+)?   23.IP address:       ^ (d{1,2}|1dd|2[0-4]d|25[0-5]). (D{1,2}|1dd|2[0-4]d|25[0-5]). (D{1,2}|1dd|2[0-4]d|25[0-5]). (d{1,2}|1dd|2[0-4]d|25[0-5]) $   24.  a regular expression that matches Chinese characters:       [/u4e00-/ u9fa5]   25. Matching double-byte characters (including Chinese characters):       [^/x00-/xff]   26.  Regular expressions that match empty rows:       /n[/s| ]*/r   27. Regular expressions that match HTML tags:       /< (. *) >.*<///1>|< (. *)  //>/   28. Regular expression:  matching the end-and-end spaces        (^/s*) | (/s*$)    29.A regular expression:       /w+ that matches an email address ([-+.] /w+) *@/w+ ([-.] /w+) */./w+ ([-.] /w+) *   30.  The regular expression:       ^[a-za-z]+://(//w+) *) (//) that matches the URL of the URL. ( w+ (-//w+) *)) * (//?//s*)?$   31.  Match account number is legal (start letter, allow 5-16 bytes, allow alphanumeric underline):        ^[a-zA-Z][a-zA-Z0-9_]{4,15}$   32.  Matching domestic phone number: