Javascript learning notes (5) Regular Expressions

Regular Expressions are often used in web development and are mainly used to verify the format of user input data. Frequently Used metacharacters include :. searches for a single character, except for line breaks and line terminologies. w matches letters, Chinese characters, numbers, and underscores. s matches blank characters (including spaces and tabs). d matches numbers; match SyntaxHighlighter. all ();

Regular Expressions are often used in web development and are mainly used to verify the format of user input data.
Frequently Used metacharacters include:
. Find a single character, except for line breaks and line terminator;
W matches letters, Chinese characters, numbers, underscores, and other symbols;
S matches blank characters (including spaces and tabs );
D. Match the number;
Match at the beginning or end of a word;
Common quantifiers include:
^ N matches any string starting with n;
N $ matches any string ending with n;
N + matches any string containing at least one n;
N * matches any string containing zero or multiple n values;
N? Matches any string containing zero or one n;
N {X} matches the string containing X n sequences;
N {X, Y} matches strings that contain X or Y n sequences;
A simple example is used to verify the mobile phone number, phone number, and email address:
Javascript code:
View sourceprint? 01 function isMobile (){

02 var mobile = document. getElementById ("mobile_phone ");

03 var num = mobile. value;

04 var reg =/^ (13 [0-9] | 186 | 188 | 150 | 151 | 158 | 159 | 147) d {8} $ /;

05 if (num = ""){

06 alert ("Enter the complete mobile phone number ");

07 mobile. focus ();

08 return false;

09} else if (reg. test (num )){

10 alert ("the entered mobile phone number is in the correct format ");

11} else {

12 alert ("enter the correct 11-digit mobile phone number ");

13 mobile. focus ();

14 return false;

15}

16}

17

18 function isEmail (){

19 var email = document. getElementById ("email ");

20 var email_value = email. value;

21 if (email_value = ""){

22 alert ("Enter the complete email address ");

23 email. focus ();

24 return false;

25} else {

26 var reg =/^ [a-zA-Z0-9] (w) + @ (w) + (.) + (com | com.cn | net | cn | net.cn | org | biz | info | gov | gov.cn | edu | edu.cn) $ /;

27 if (reg. test (email_value )){

28 alert ("the entered email address format is correct ");

29} else {

30 alert ("enter the correct email format ");

31 email. focus ();

32 return false;

33}

34}

35}

36

37 function isPhone (){

38 var phone = document. getElementById ("phone ");

39 var phone_value = phone. value;

40 if (phone_value = ""){

41 alert ("Enter the complete landline number ");

42 phone. focus ();

43 return false;

44} else {

45 var reg =/^ [(]? 0d {2, 3} [)]? S * [-]? S * d {87989898} $/; // 010-01098989898 0712 (8989898) 23343434 010-All landline numbers in these formats are

46 if (reg. test (phone_value )){

47 alert ("the entered landline number is correct ");

48} else {

49 alert ("Incorrect landline number format ");

50 phone. focus ();

51 return false;

52}

53}

54}

Some HTML code:
View sourceprint? 01

02Mobile Machine

03

04

05

06

07Seat Machine

08

09

10

11

12Mail Box

13

14

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