使用正则表达式匹配日期和时间

Question

I am trying to write a regex that matches the date and time in this format - d/m/YH:m am/pm. For example, 1/2/2020 1.30pm

This is the regex I am using but it does not match the date and time specified in the example -

$value = '1/2/2020 1.30pm';
if(preg_match("/^[0-9]{1,2}/[0-9]{1,2}/[0-9]{4} (0\d|1[0-2]):([0-5]\d)(?::((?2)))?\h*([ap]m)? $/", $value) === 0) {
     return false;
}else{
     return true;
}

Please kindly help correct my mistakes on the regex expression

Answer 1

As others have pointed out, there are lots of ways to validate the date, in addition to matching; you could find some different approaches. Here is a regex that will match your date, regardless of what you use to separate the numbers. \W indicates any "non-word character" will match -, or / or anything so long as it isn't a letter, digit or underscore. The? will match 0 or 1, and the * will match zero or more.

^\d+\W\d+\W\d+\s+\d+\W?\d+\w*

Will match all of these:

01/02/2020 11:45am

01-02-2020 10.33pm

1-23-68 2345

09/30/2323 23:15

Cheers! Kylie

Answer 2

If you don't care about some freedom in the format (like accepting both pm and PM ), you can use DateTime::createFromFormat() :

$dateTime = DateTime::createFromFormat('j/n/Y g.ia', $value);
$isValid = $dateTime !== false;