65 most commonly used regular expressions

1. Expression of check digit

1 Number: ^[0-9]*$

2 Number of n digits: ^\d{n}$

3 Number of at least n digits: ^\d{n,}$

4 mn digits Numbers of : ^\d{m,n}$

5 Numbers starting with zero and non-zero: ^(0|[1-9][0-9]*)$

6 Numbers starting with non-zero with up to two decimal places : ^([1-9][0-9]*)+(.[0-9]{1,2})?$

7 Positive or negative number with 1-2 decimal places: ^(\-)? \d+(\.\d{1,2})?$

8 Positive numbers, negative numbers, and decimals: ^(\-|\+)?\d+(\.\d+)?$

9 Positive numbers with two decimal places Real numbers: ^[0-9]+(.[0-9]{2})?$

10 Positive real numbers with 1~3 decimal places: ^[0-9]+(.[0-9]{1, 3})?$

11 Non-zero positive integer: ^[1-9]\d*$ or ^([1-9][0-9]*){1,3}$ or ^\+?[1 -9][0-9]*$

12 Non-zero negative integer: ^\-[1-9][]0-9"*$ or ^-[1-9]\d*$

13 Non-negative integer: ^\d+$ or ^[1-9]\d*|0$

14 non-positive integer: ^-[1-9]\d*|0$ or ^((-\d+)|(0+))$

15 Non-negative floating point number: ^\d+(\.\d+)?$ or ^[1-9]\d*\.\d*|0\.\d*[1-9]\d*|0? \.0+|0$

16 Non-positive floating-point numbers: ^((-\d+(\.\d+)?)|(0+(\.0+)?))$ or ^(-([1-9]\d*\.\ d*|0\.\d*[1-9]\d*))|0?\.0+|0$

17 Positive float: ^[1-9]\d*\.\d*|0 \.\d*[1-9]\d*$ or ^(([0-9]+\.[0-9]*[1-9][0-9]*)|([0-9 ]*[1-9][0-9]*\.[0-9]+)|([0-9]*[1-9][0-9]*))$

18 Negative float: ^ -([1-9]\d*\.\d*|0\.\d*[1-9]\d*)$ or ^(-(([0-9]+\.[0-9 ]*[1-9][0-9]*)|([0-9]*[1-9][0-9]*\.[0-9]+)|([0-9]* [1-9][0-9]*)))$

19 Floating point: ^(-?\d+)(\.\d+)?$ or ^-?([1-9]\d*\.\ d*|0\.\d*[1-9]\d*|0?\.0+|0)$

Second, the expression of check character

1 Chinese characters: ^[\u4e00-\u9fa5]{0, }$

2 English and numbers: ^[A-Za-z0-9]+$ or ^[A-Za-z0-9]{4,40}$

3 All characters of length 3-20: ^.{3 ,20}$

4 A string consisting of 26 English letters: ^[A-Za-z]+$

5 A string consisting of 26 uppercase English letters: ^[AZ]+$

6 26 lowercase English letters String composed of: ^[az]+$

7 String composed of numbers and 26 English letters: ^[A-Za-z0-9]+$

8 String composed of numbers, 26 English letters or underscores : ^\w+$ or ^\w{3,20}$

9 Chinese, English, numbers including underscores: ^[\u4E00-\u9FA5A-Za-z0-9_]+$

10 Chinese, English, numbers but not including underscores and other symbols: ^[\u4E00-\u9FA5A-Za-z0- 9]+$ or ^[\u4E00-\u9FA5A-Za-z0-9]{2,20}$

11 You can enter characters including ^%&',;=?$\": [^%&',; =?$\x22]+

12 It is forbidden to input characters containing ~: [^~\x22]+

3. Special demand expression

1 Email address: ^\w+([-+.]\w+)*@\w+([ -.]\w+)*\.\w+([-.]\w+)*$

2 Domain name: [a-zA-Z0-9][-a-zA-Z0-9]{0,62}(/ .[a-zA-Z0-9][-a-zA-Z0-9]{0,62})+/.?

3 InternetURL: [a-zA-z]+://[^\s]* or ^http://([\w-]+\.)+[\w-]+(/[\w-./?%&=]*)?$

4 Mobile number: ^(13[0- 9]|14[5|7]|15[0|1|2|3|5|6|7|8|9]|18[0|1|2|3|5|6|7|8|9 ])\d{8}$

5 Phone numbers ("XXX-XXXXXXX", "XXXX-XXXXXXXX", "XXX-XXXXXXX", "XXX-XXXXXXXX", "XXXXXXX" and "XXXXXXXX"): ^(\(\d {3,4}-)|\d{3.4}-)?\d{7, 8}$

6 Domestic phone numbers (0511-4405222, 021-87888822): \d{3}-\d{8}|\d{4}-\d{7}

7 ID number (15 digits, 18 digits): ^\d{15}|\d{18}$

8 Short ID number (end with numbers, letter x): ^([0-9]){7, 18}(x|X)?$ or ^\d{8,18}|[0-9x]{8,18}|[0-9X]{8,18}?$

9 Is the account number legal (begins with a letter, 5-16 bytes are allowed, alphanumeric underscores are allowed): ^[a-zA-Z][a-zA-Z0-9_]{4,15}$

10 Password (starting with a letter, length between 6~18 , can only contain letters, numbers and underscores): ^[a-zA-Z]\w{5,17}$

11 Strong password (must contain a combination of uppercase and lowercase letters and numbers, no special characters, and a length of 8- 10): ^(?=.*\d)(?=.*[az])(?=.*[AZ]).{8,10}$

12 Date format: ^\d{4}- \d{1,2}-\d{1,2}

13 12 months of a year (01~09 and 1~12): ^(0?[1-9]|1[0-2])$

14 31 days of a month (01~09 and 1~31): ^((0?[1-9])|((1|2)[0-9])|30|31)$

15 money input Format:

16 1. There are four representations of money we can accept: "10000.00" and "10,000.00", and "10000" and "10,000" without "cents": ^[1-9][0-9]* $

17 2. This means any number that does not start with 0, however, it also means that a character "0" is not passed, so we take the following form: ^(0|[1-9][0-9] *)$

18 3. A 0 or a number that does not start with 0. We can also allow a negative sign at the beginning: ^(0|-?[1-9][0-9]*)$

19 4. This means a 0 or a number that may be negative and not 0 at the beginning. Let the user start with 0. Also remove the negative sign, because money can never be negative. What we want to add next is Explain the possible fractional part: ^[0-9]+(.[0-9]+)?$

20 5. It must be noted that there should be at least 1 digit after the decimal point, so "10." is not passed , but "10" and "10.2" are passed: ^[0-9]+(.[0-9]{2})?$

21 6. This way we stipulate that there must be two digits after the decimal point, if you think too much Harsh, it can be like this: ^[0-9]+(.[0-9]{1,2})?$

22 7. This allows the user to write only one decimal place. Now we should consider the comma in the number , we can do this: ^[0-9]{1,3}(,[0-9]{3})*(.[0-9]{1,2})?$

23 8.1 to 3 numbers, Followed by any comma + 3 digits, the comma becomes optional, not required: ^([0-9]+|[0-9]{1,3}(,[0-9]{3})* )(.[0-9]{1,2})?$

24 Note: This is the final result, don't forget that "+" can be replaced with "*" if you think empty strings are acceptable (strange, Why?) Finally, don't forget to remove the backslash when using the function, the general error is here

25 xml file: ^([a-zA-Z]+-?)+[a-zA-Z0- 9]+\\.[x|X][m|M][l|L]$

26 Regular expression for Chinese characters: [\u4e00-\u9fa5]

27 Double-byte characters: [^\x00-\xff ] (including Chinese characters, can be used to calculate the length of a string (a double-byte character counts as 2, ASCII character counts as 1))

28 Regular expression for blank lines: \n\s*\r (can be used to delete blank lines)

29 The regular expression of HTML tags: <(\S*?)[^>]*>.*?</\1>|<.*? /> (The version circulating on the Internet is too bad, and the above is only partially , still powerless for complex nested tags)

Regular expression for 30 leading and trailing whitespace characters: ^\s*|\s*$ or (^\s*)|(\s*$) (can be used to delete the first line of a line Trailing whitespace characters (including spaces, tabs, form feeds, etc.), very useful expressions)

31 Tencent QQ number: [1-9][0-9]{4,} (Tencent QQ number from 10000 Start)

32 China Postal Code: [1-9]\d{5}(?!\d) (China Postal Code is 6 digits)

33 IP Address: \d+\.\d+\.\d+\.\d+ (useful when extracting IP address)

34 IP address: ((?:(?:25[0-5]|2[0-4]\\d|[01]?\\d?\\d)\\. ){3}(?:25[0-5]|2[0-4]\\d|[01]?\\d?\\d))