Question

找到此技术来验证电子邮件地址是否正确。

function check_email($email) {  
        if( (preg_match('/(@.*@)|(\.\.)|(@\.)|(\.@)|(^\.)/', $email)) || 
            (preg_match('/^.+\@(\[?)[a-zA-Z0-9\-\.]+\.([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/',$email)) ) { 
             return true;
        } else {
             return false;
        }       
    }

我是php的新手。这个大正则表达式命令意味着什么？

Answer 1

这个大正则表达式命令意味着什么？

模式＃1细分：

Movies : A WALK,DRAGONBALL
Users : 1 20
Movies : JAMES BOND,MISSION
Users : 6 7

在我看来，第一种模式看起来像绝对无用的垃圾。

模式2细分：

/           #start of pattern delimiter
(@.*@)      #Capture Group #1: match an @ sign, then zero or more (as many as possible) of any non-newline character, then another @ sign
|           #or
(\.\.)      #Capture Group #2: match a literal dot, then another literal dot
|           #or
(@\.)       #Capture Group #3: match an @ sign, then a literal dot
|           #or
(\.@)       #Capture Group #4: match a literal dot, then an @ sign
|           #or
(^\.)       #Capture Group #5: match the start of the string, then a literal dot
/           #end of pattern delimiter

我不推荐这些模式。

如果您要验证电子邮件，可以在StackOverflow周围使用更好的模式，或者您可以使用/ #start of pattern delimiter ^ #match start of string .+ #match any non-newline character one or more times (as much as possible) \@ #match @ (the \ is an escaping character which is not necessary) (\[?) #Capture Group #1: match an opening square bracket zero or one time [a-zA-Z0-9\-\.]+ #match one or more (as much as possible) of the following characters: lowercase letters, uppercase letters, digits, hyphens, and dots (the \ before the . is an escaping character which is not necessary) \. #match a literal dot ( #start Capture Group #2 [a-zA-Z]{2,4} #match any uppercase or lowercase letter 2, 3, or 4 times | #or [0-9]{1,3} #match any digit 1, 2, or 3 times ) #end Capture Group #2 (\]?) #Capture Group #3: match a closing square bracket zero or one time $ #match the end of the string / #end of pattern delimiter电话。

研究这个字符串：

filter_var()

这个正则表达式是什么样的“/^.+\@(\\？）[azA-Z0-9 \ - \。] + \。（[a-zA-Z] {2,4} | [0 -9] {1,3}）（\]？）$ /”

1 个答案: