Small issues that js regular expressions are easy to ignore

1. special characters in brackets [] do not need to be escaped, such as [/], [.], [*], and [?]. And [+] can directly match the corresponding characters .*? +. The test result is as follows:

 

Therefore, the/[d.]/regular expression matches a number or character ".", which is equivalent to/[d.]/

Ii. Differences between match () and exec ()

The main difference between the two is that the regular expression sets the GLobal IDEntifier g.

If no identifier is set to G', the result of calling string.match(regexp;is the same as that of calling regexp.exe c (string,

Only the first successful match is given in the result of objective c (string.

The regexp. lastIndex attribute is used to record the starting position of the next matching. The test is as follows:

PS: note that lastIndex only applies to exec () and test () methods. string. match (regexp) does not affect the lastIndex attribute of regexp.

I have added my favorites from the Internet, but they are all excellent products. They are specialized in verifying mobile phone numbers and phone numbers.

The Code is as follows:

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Function checkPhone (phone) { // Verify the phone number, including the phone number 153,159 If (phone = ""){ Alert ("the phone number cannot be blank! "); Return false; } If (phone! = ""){ Var p1 =/^ ([0 +] d {2, 3 }-)? (0d {2, 3 })-)? (D {7, 8}) (-(d {3 ,}))? $ /; Var me = false; If (p1.test (phone) me = true; If (! Me ){ // Alert ('Sorry, www. bKjia. c0m. The phone number you entered is incorrect. Use-to separate the area code from the phone number '); Return false; } } Return true; }

 
Mobile phone number verification

The Code is as follows:

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String. prototype. isTel = function () { // "Compatible format: Country Code bKjia. c0m (2 to 3 digits)-area code (2 to 3 digits)-telephone number (7 to 8 digits)-extension number (3 digits )" // Return (/^ ([0 +] d {2, 3 }-)? (0d {2, 3 })-)? (D {7, 8}) (-(d {3 ,}))? $/. Test (this. Trim ())); Return (/^ ([0 +] d {2, 3 }-)? (0d {2, 3})-) (d {7, 8}) (-(d {3 ,}))? $/. Test (this. Trim ())); } // Verify the mobile phone number String. prototype. isMobile = function (){ Return (/^ (? : 13d | 15 [89])-? D {5} (d {3} | * {3}) $/. test (this. Trim ())); }

Phone number verification

The Code is as follows:	Copy code
Function CheckNum () {// phone Verification Var InputValue = document. gsjbxxBean. dh. value; Var reg =/^ ([0-9] | [-]) + $/g; Var isValid Isvalid1_reg.exe c (InputValue) If (! IsValid ){ Return false } Return true }

Check the phone number

The Code is as follows:	Copy code
Function isTel (str ){ Var reg =/^ ([0-9] [-]) + $/g; If (str. length <7 str. length> 18 ){ Return false; } Else { Return reg.exe c (str ); } }