Shell Regular Expression Detail _ regular expression

Shell-Used regular expressions

"^\d+$"//non-negative Integer (positive integer + 0)
"^[0-9]*[1-9][0-9]*$"//Positive integer
"^ ((-\d+) | (0+)) $ "//non-positive integer (negative integer + 0)
"^-[0-9]*[1-9][0-9]*$"//Negative integer
"^-?\d+$"//Integer
"^\d+ (\.\d+)? $"//nonnegative floating-point number (positive float + 0)
"^ ([0-9]+\. [0-9]*[1-9][0-9]*) | ([0-9]*[1-9][0-9]*\. [0-9]+) | ([0-9]*[1-9][0-9]*)] $ "//Positive floating-point number
"^ ((-\d+ (\.\d+)?) | (0+ (\.0+)) $ "//non-positive floating-point number (negative floating-point number + 0)
^ (-([0-9]+\. [0-9]*[1-9][0-9]*) | ([0-9]*[1-9][0-9]*\. [0-9]+) | ([0-9]*[1-9][0-9]*))] $ "//negative floating-point number
"^ (-?\d+) (\.\d+)? $"//floating-point number
"^[a-za-z]+$"//A string of 26 English letters
"^[a-z]+$"//A string of 26 uppercase letters
"^[a-z]+$"///a string consisting of 26 lowercase letters
"^[a-za-z0-9]+$"//A string of numbers and 26 English letters
"^\w+$"//A string of numbers, 26 English letters, or underscores
"^[\w-]+ (\.[ \w-]+) *@[\w-]+ (\.[ \w-]+) +$ "//email address
"^[a-za-z]+://(\w+ (-\w+) *) (\. ( \w+ (-\w+) *)) * (\?\s*) $ "//url
/^ (D{2}|d{4})-((0 ([1-9]{1})) | ( 1[1|2])-(([0-2] ([1-9]{1})) | ( 3[0|1]) $///year-month-day
/^ ((0 ([1-9]{1})) | (1[1|2]) /(([0-2] ([1-9]{1})] | (3[0|1]) /(D{2}|d{4}) $///month/day/year
"^ ([w.] +) @ ([[0-9]{1,3}. [0-9] {1,3}. [0-9] {1,3}.) | (([w-]+.) +)) ([a-za-z]{2,4}| [0-9] {1,3}) (]?) $ "//emil
/^((\+? [0-9] {2,4}\-[0-9]{3,4}\-) | ([0-9]{3,4}\-)]? ([0-9]{7,8}) (\-[0-9]+) $//Telephone number
"^ (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]) $ "//IP address

Matching regular expressions for Chinese characters: [\U4E00-\U9FA5]
Match Double-byte characters (including Chinese characters): [^\x00-\xff]
A regular expression that matches a blank row: \n[\s|] *\r
Regular expression matching HTML tags:/< (. *) >.*<\/\1>|< (. *) \/>/
Matching a regular expression with a trailing space: (^\s*) | (\s*$)
Regular expression matching an email address: \w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *
A regular expression that matches URL URLs: ^[a-za-z]+://(\\w+ (-\\w+) *) (\ \\w+ (-\\w+) *)) * (\\?\\s*)? $
Match account number is legal (beginning of letter, allow 5-16 bytes, allow alphanumeric underline): ^[a-za-z][a-za-z0-9_]{4,15}$
Match domestic phone number: (\d{3}-|\d{4}-)? (\d{8}|\d{7})?
Matching Tencent QQ Number: ^[1-9]*[1-9][0-9]*$

Metacharacters and its behavior in the context of regular expressions:

\ marks the next character as a special character, or a literal character, or a back reference, or a octal escape character.


^ matches the start position of the input string. If the multiline property of the RegExp object is set, ^ also matches the position after ' \ n ' or ' \ R '.


$ matches the end position of the input string. If the multiline property of the RegExp object is set, the $ also matches the position before ' \ n ' or ' \ R '.


* Match the preceding subexpression 0 or more times.


+ matches the preceding subexpression one or more times. + is equivalent to {1,}.


? Match the preceding subexpression 0 times or once.? is equivalent to {0,1}.


{n} n is a non-negative integer that matches the determined N times.


{N,} n is a non-negative integer that matches at least n times.


{n,m} m and n are non-negative integers, where n <= m. Matches n times at least and matches up to M times. You cannot have spaces between commas and two numbers.


? When the character is immediately following any of the other qualifiers (*, +,?, {n}, {n,}, {n,m}), the matching pattern is not greedy. Non-greedy patterns match as few strings as possible, while the default greedy pattern matches as many of the searched strings as possible.


. Matches any single character except "\ n". To match any character including ' \ n ', use a pattern like ' [. \ n] '.
(pattern) matches the pattern and gets the match.


(?:p Attern) matches pattern but does not get matching results, which means that this is a non fetch match and is not stored for later use.


(? =pattern) forward lookup, matching the find string at the beginning of any string matching pattern. This is a non-fetch match, that is, the match does not need to be acquired for later use.


(?! pattern) Negative forward check, contrary to (? =pattern) Effect


X|y matches x or Y.


[XYZ] Character set combination.


[^XYZ] Negative character set combination.


[A-z] character range that matches any character within the specified range.


[^a-z] A negative character range that matches any character that is not in the specified range.


\b Matches a word boundary, which refers to the position between the word and the space.


\b Matches a non word boundary.


\CX matches the control characters indicated by X.


\d matches a numeric character. equivalent to [0-9].


\d matches a non-numeric character. equivalent to [^0-9].


\f matches a page feed character. Equivalent to \x0c and \CL.


\ n matches a newline character. Equivalent to \x0a and \CJ.


\ r matches a carriage return character. Equivalent to \x0d and \cm.


\s matches any white space character, including spaces, tabs, page breaks, and so on. equivalent to [\f\n\r\t\v].


\s matches any non-white-space character. equivalent to [^ \f\n\r\t\v].


\ t matches a tab character. Equivalent to \x09 and \ci.


\v matches a vertical tab. Equivalent to \x0b and \ck.


\w matches any word character that includes an underscore. Equivalent to ' [a-za-z0-9_] '.


\w matches any non word character. Equivalent to ' [^a-za-z0-9_] '.


\XN matches N, where n is the hexadecimal escape value. The hexadecimal escape value must be a determined two digits long.


\num matches num, where num is a positive integer. A reference to the match that was obtained.


\ n identifies a octal escape value or a back reference. N is a back reference if you have at least N obtained subexpression before. Otherwise, if n is an octal number (0-7), then N is an octal escape value.


\NM identifies a octal escape value or a back reference. NM is a \nm if at least one of the preceded by the at least NM gets the subexpression before the If there are at least N fetches before \nm, then N is a back reference followed by a literal m. If all the preceding conditions are not satisfied, if both N and M are octal digits (0-7), then \nm will match octal escape value nm.


\NML if n is an octal number (0-3) and both M and L are octal digits (0-7), then the octal escape value NML is matched.


\un matches N, where N is a Unicode character represented in four hexadecimal digits.

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


Match Double-byte characters (including Chinese characters): [^x00-xff]


A regular expression that matches a blank row: n[s|] *r


Regular expression matching HTML tags:/< (. *) >.*</1>|< (. *)/>/


Matching a regular expression with a trailing space: (^s*) | (s*$)


Regular expression matching an email address: w+ ([-+.] w+) *@w+ ([-.] w+) *.w+ ([-.] w+) *


A regular expression that matches URL URLs: http://([w-]+.) +[w-]+ (/[w-/?%&=]*)?

Use regular expressions to restrict the entry of text boxes in a Web page's form:

The regular expression limit can only be entered in Chinese: onkeyup= "value=value.replace (/[^u4e00-u9fa5]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^u4e00-u9fa5]/g, ")"


Only full-width characters can be entered with regular expression restrictions: onkeyup= "Value=value.replace (/[^uff00-uffff]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ' , Clipboarddata.getdata (' text '). Replace (/[^uff00-uffff]/g, ")"


Only numbers can be entered with regular expression restrictions: onkeyup= "Value=value.replace (/[^d]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^d]/g, ")"


Only numbers and English can be entered with regular expression restrictions: onkeyup= "Value=value.replace (/[w]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^d]/g, ")"

Regular expressions of common use

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


Match Double-byte characters (including Chinese characters): [^\x00-\xff]


A regular expression that matches a blank row: \n[\s|] *\r


Regular expression matching HTML tags:/< (. *) >.*<\/\1>|< (. *) \/>/


Matching a regular expression with a trailing space: (^\s*) | (\s*$)


Regular expression matching IP address:/(\d+) \. (\d+) \. (\d+) \. (\d+)/g//


Regular expression matching an email address: \w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *


A regular expression that matches URL URLs: http://(/[\w-]+\.) +[\w-]+ (/[\w-/?%&=]*)?

SQL statement: ^ (select|drop|delete|create|update|insert). *$

1, nonnegative integer: ^\d+$


2, positive integer: ^[0-9]*[1-9][0-9]*$


3, non-positive integer: ^ (-\d+) | ( 0+)) $


4, negative integer: ^-[0-9]*[1-9][0-9]*$


5. Integer: ^-?\d+$


6, nonnegative floating-point number: ^\d+ (\.\d+)? $


7, Positive 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]*)] $


8. Non-positive floating-point number: ^ ((-\d+\.\d+)?) | (0+ (\.0+)) $


9. Negative floating point number: ^ (-(positive floating-point number regular)) $


10. English string: ^[a-za-z]+$


11, English capital string: ^[a-z]+$


12. English lowercase string: ^[a-z]+$


13, English character number string: ^[a-za-z0-9]+$


14, the English numeral adds the underline string: ^\w+$


15. E-mail address: ^[\w-]+ (\.[ \w-]+) *@[\w-]+ (\.[ \w-]+) +$


16, url:^[a-za-z]+://(\w+ (-\w+) *) ( \w+ (-\w+) *)) * (\?\s*)? $
Or: ^http:\/\/[a-za-z0-9]+\. [a-za-z0-9]+[\/=\?%\ -&_~ ' @[\]\ ': +!] * ([^& lt;>\ "\"]) *$


17. Postal Code: ^[1-9]\d{5}$


18, Chinese: ^[\u0391-\uffe5]+$


19. Telephone Number: ^ ((\d{2,3}\)) | ( \d{3}\-))? (\ (0\d{2,3}\) |0\d{2,3}-)? [1-9] \d{6,7} (\-\d{1,4})? $


20. Mobile Number: ^ ((\d{2,3}\)) | ( \d{3}\-))? 13\d{9}$


21, double-byte characters (including Chinese characters): ^\x00-\xff

22, matching the end of the space: (^\s*) | (\s*$) (Trim function like VBScript)

23, Matching HTML tags:< (. *) >.*<\/\1>|< (. *) \/>

24, matching blank line: \n[\s|] *\r

25, extract the information in the network link: (h| H) (r| R) (e| E) (f| F) *= * (' | ')? (\w|\\|\/|\.) + (' | ' | *|>)?

26, the extraction of information in the mail address: \w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *

27, extract the information in the picture link: (s| S) (r| R) (c| C) *= * (' | ')? (\w|\\|\/|\.) + (' | ' | *|>)?

28, extract the information in the IP address: (\d+) \. (\d+) \. (\d+) \. (\d+)

29, the extraction of information in China Mobile phone number: (*0*13\d{9)

30, extract the information in China fixed telephone number: (\ (\d{3,4}\) |\d{3,4}-|\s)? \d{8}

31, the extraction of information in China telephone number (including mobile and fixed telephone): (\ (\d{3,4}\) |\d{3,4}-|\s)? \d{7,14}

32, the extraction of information in China's postal code: [1-9]{1} (\d+) {5}

33, extract the information in the floating-point number (that is, decimal): (-?\d*) \.? \d+

34, the extraction of any number of information: (-?\d*) (\.\d+)?

35, IP: (\d+) \. (\d+) \. (\d+) \. (\d+)

36, telephone area code:/^0\d{2,3}$/

37, Tencent QQ number: ^[1-9]*[1-9][0-9]*$

38. Account number (beginning of letter, allow 5-16 bytes, allow alphanumeric underline): ^[a-za-z][a-za-z0-9_]{4,15}$

39, Chinese, English, numerals and underscores: ^[\u4e00-\u9fa5_a-za-z0-9]+$

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