JS Regular expression verification account, mobile phone number, phone, and e-mail

Verify that your account is legitimate
Validation rules: Letters, numbers, underscores, letters beginning with 4-16 digits.

function CheckUser (str) {    var re =/^[a-za-z]\w{3,15}$/;    if (Re.test (str)) {        alert ("correct");    } else{        alert ("error");    }          } CheckUser ("Jihua_cnblogs");//Call

Verify your phone number
Validation rule: 11 digits, starting with 1.

function  Checkmobile (str) {    var  re =/^1\d{10}$/    if (re.test (str)) {        alert ("correct");    } else {        alert ("Error");}    } Checkmobile (' 13800138000 '); Call Checkmobile (' 139888888889 ');//Error example

Verify phone number
Validation rules: Area code + number, area code starting with 0, 3-bit or 4-bit
Numbers are made up of 7-bit or 8-digit numbers
There can be no connector between the area code and the number, or a "-" connection
such as 01088888888,010-88888888,0955-7777777

function Checkphone (str) {    var re =/^0\d{2,3}-?\d{7,8}$/;    if (Re.test (str)) {        alert ("correct");    } else{        alert ("Error");}    } Checkphone ("09557777777");//Call

Verify Mailbox
Validation rules: Leave your email address in the "first part @ Second part"
The first part: By letter, number, underline, short line "-", Dot "." Composition
Part two: For a domain name, the domain name consists of letters, numbers, short-term "-", the domain name suffix,
and the domain name suffix is generally. xxx or. xxx.xx, a domain name suffix is generally 2-4-bit, such as cn,com,net, now the domain name will be more than 4 bit

function Checkemail (str) {    var re =/^ (\w-*\.*) [email protected] (\w-?) + (\.\w{2,}) +$/    if (re.test (str)) {        alert ("correct");    } else{        alert ("Error");}    } Checkemail ("[email protected]");//Call

JS Regular expression verification account, mobile phone number, phone, and e-mail