PHP regex: ^ and $ vs \A and \z

7月

2日,

2019年

When tempted to do this:



$name = "joe";

if (preg_match('/^[a-zA-Z]+$/', $name) {

}

Chances are, you probably want use this instead:



if (preg_match('/\A[a-zA-Z]+\z/', $name) {

}

Why?

Use of ^ is OK, but $ matches line break characters.
So,



$name = "joe¥n";

if (preg_match('/^[a-zA-Z]+$/', $name) {

    echo "match!";

}

Will display "match!" - which is probably something you don't want.

#php

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