First attach the Code
Copy Code code as follows:
^[_.0-9a-z-]+@ ([0-9a-z][0-9a-z-]+.) +[a-z]{2,3}$
In this regular expression, "+" means one or more occurrences of the preceding string; "^" means that the next string must appear at the beginning, and "$" indicates that the previous string must appear at the end;
“.” That is, ".", where "" is an escape character; "{2,3}" means that the preceding string can appear 2-3 consecutive times. "()" means that the contained content must appear in the target object at the same time. "[_.0-9a-z-]" means any character contained in "_", ".", "-", letters from A to Z range, numbers from 0 to 9;
Thus, this regular expression can be translated as follows:
"The following characters must be at the beginning (^)", "the character must be contained in" _ ",". ","-", letters from A to Z range, numbers from 0 to 9 ([_.0-9a-z-]), and" preceded by at least one (+) ", @," The string consists of a letter that is contained in the range from A to Z, starts with a character from a number in the range 0 through 9, followed by at least one of the characters contained in "-", any letter from A to Z range, from 0 to 9, and finally. End ([0-9a-z][0-9a-z- ]+.) "", "the preceding character appears at least once (+)", "the letter from A to Z appears 2-3 times, and ends with it ([a-z]{2,3}$)"
Copy Code code as follows:
function Is_valid_email ($email, $test _mx = False)
{
if (eregi ("^" [_a-z0-9-]+) (. [ _a-z0-9-]+) *@ ([a-z0-9-]+) (. [ a-z0-9-]+) * (. [ a-z]{2,4}) [Wind_phpcode_0]quot;, $email))
if ($test _mx)
{
List ($username, $domain) = Split ("@", $email);
Return Getmxrr ($domain, $mxrecords);
}
Else
return true;
Else
return false;
}
Domain names are composed of specific character sets, English letters, numbers, and "-" (that is, hyphens or minus signs) of each country's text, but neither the beginning nor the end can contain "-", "-" and "-" cannot appear continuously. The letters in the domain name are not case-insensitive. The domain name can be up to 60 bytes (including suffix. com,. NET,. org, and so on).
/^[a-z] ([a-z0-9]*[-_]?[ a-z0-9]+) *@ ([a-z0-9]*[-_]?[ a-z0-9]+) +[.] [A-z] {2,3} ([.] [A-z] {2})? $/i;
/content/I forms a case-insensitive regular expression;
^ Match start
$ match End
[A-z] e-mail prefix must be an English letter beginning
([A-z0-9]*[-_]? [a-z0-9]+) * and _a_2, AAA11, _1_a_2 match, and A1_, Aaff_33a_, A__aa mismatch, if it is a null character, is also a match, * represents 0 or more.
* Represents 0 or more preceding characters.
[a-z0-9]* matches 0 or more English letters or numbers
[-_]? Match 0 or 1 "-" because "-" cannot appear continuously
[a-z0-9]+ matches 1 or more English letters or numbers, because "-" can not be done as the end
@ must have a @
([A-z0-9]*[-_]? [a-z0-9]+] + see above ([a-z0-9]*[-_]?[ a-z0-9]+) * explanation, but cannot be null, + represents one or more.
[.] The special character (.) As a normal character
[A-z] {2,3} matches 2 to 3 English letters, typically COM or net.
([.] [A-z] {2})? Match 0 or 1 [.] [A-z] {2} (for example, CN, etc.) I don't know. com.cn the last part is not all two digits, if not please modify {2} to {starting words, end words}
Perfect e-mail regular expression, with detailed explanation, please help test! 2. Extract the email in the string:
Copy Code code as follows:
<?php
function Getemail ($STR) {
$pattern = "/([A-z0-9]*[-_.]? [a-z0-9]+) *@ ([a-z0-9]*[-_]?[ a-z0-9]+) +[.] [A-z] {2,3} ([.] [A-z] {2})? /I ";
Preg_match_all ($pattern, $str, $EMAILARR);
return $EMAILARR [0];
}
$emailstr = "9999@qq.com.cn I am not the M VI Place to open IID mailing list: fuyongjie@163.com and hh@qq.com;. ;;, fuyongjie.100@yahoo.com,fu-1999@sina.com ";
$EMAILARR = Getemail ($EMAILSTR);
echo "<pre>";
Print_r ($EMAILARR);
echo "</pre>";
?> print as follows:
Array
(
[0] =>9999@qq.com.cn
[1] =>fuyongjie@163.com
[2] =>hh@qq.com
[3] =>fuyongjie.100@yahoo.com
[4] =>fu-1999@sina.com
3. Comparison: In the 2nd, there are no 1th ^ and $;
Look at the example again
Copy Code code as follows:
function Funcemail ($STR)/mailbox Regular expression
{
return (Preg_match ('/^[_.0-9a -z-a-z-]+@ ([0-9a-z][0-9a-z-]+.) +[a-z]{2,4}$/', $str))? True:false;
}//authentication Method One
$str = "qbcd@126.com.cn";
Preg_match (/^[0-9a-z]+@ ([0-9a-z]+) [.]) +[a-z]{2,3}$/", $str, $re);
Print_r ($re);//mailbox Authentication two
if (eregi ("^[_.0-9a-z-]+@") ([0-9a-z][0-9a-z-]+.) +[a-z]{2,3}$ ", $email)) {
echo" your e-mail through preliminary check ";
}//The third mailbox authentication method
if (ereg ("/^[a-z") ([A-z0-9]*[-_.]? [a-z0-9]+) *@ ([a-z0-9]*[-_]?[ a-z0-9]+) +[.] [A-z] {2,3} ([.] [A-z] {2})? $/i; ", $email)) {
echo" your email address is correct! ";}
else{
Echo "Please try again!";
}
