Regular expression Verification mailbox phone number, etc.

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

function CheckUser () {

var str = document.getElementById ("User");
var re =/^[a-za-z]\w{3,15}$/;
if (Re.test (str)) {
Alert ("correct");
}else{
Alert ("Error");
}
}
CheckUser ("");//Call

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

function  Checkmobile () {
var str = document.getElementById ("mobile");    var  re =/^1\d{10}$/    if (re.test (str)) {        alert ("correct");    } else {        alert ("Error");    

Verify Mailbox

function Checkemail () {    var str = document.getElementById ("email");     var re =/^[a-za-z0-9][email protected][a-za-z0-9]+ (\.[ a-za-z0-9]+) +$/      if (str! = ""       )         {if  (Re.test (str))        {              Alert ("correct");           }Else          {              alert ("error");  }}} Checkemail ();       

　

Regular expression Verification mailbox phone number, etc.