Regex for date

[phily245]

Hi,

I'm using the JQuery UI datepicker to insert a date into a form field, but I need validation in case the user enters the date by hand. The date needs to be dd-mm-yyyy. I currently have this:

<?php
if(!preg_match('/^\d{2}\/\d{2}\/\d{4}$/', $expiryDate)) {
$issue = "9";
return $issue;
}
if(!preg_match('/^\d{2}\/\d{2}\/\d{4}$/', $startDate)) {
$issue = "9";
return $issue;
}
?>

But it's not working and I'm pretty sure its the regex.

[xyph]

You're checking for forward slashes in the RegEx, not dashes.

[phily245]

*FACEPALM*

[Pikachu2000]

You don't want to allow the user to enter a date freehand anyhow. Use <select> fields as the <noscript> alternative. Otherwise, someone will enter April 12, 2011 as 12-04-2011.

[phily245]

Thanks for the advice. I changed my regex to the following code, but it still wouldn't work.

 

<?php
        if(!preg_match('/^\d{2}-\d{2}-\d{4}$/', $expiryDate)) {
	$issue = "9";
	return $issue;
}
        if(!preg_match('/^\d{2}-\d{2}-\d{4}$/', $startDate)) {
	$issue = "9";
	return $issue;
}?>

[joe92]

Otherwise, someone will enter April 12, 2011 as 12-04-2011.

...that's the desired format

 

Place the digit character set in character classes if you are looking for repetition;

<?php
        if(!preg_match('/^[\d]{2}-[\d]{2}-[\d]{4}$/', $expiryDate)) {
	$issue = "9";
	return $issue;
}
        if(!preg_match('/^[\d]{2}-[\d]{2}-[\d]{4}$/', $startDate)) {
	$issue = "9";
	return $issue;
}
?>

 

Also, thats two if's returning the same result that could be executed on the same line;

<?php
        if(!preg_match('/^[\d]{2}-[\d]{2}-[\d]{4}$/', $expiryDate) or !preg_match('/^[\d]{2}-[\d]{2}-[\d]{4}$/', $startDate)) {
	$issue = "9";
	return $issue;
}
?>

 

Furthermore, you might want to allow for people entering the date as dd/mm/yyyy or dd.mm.yyyy so you might want to include another character set for the separation sections instead of just a dash, e.g. [./\-].

 

Hope this helps,

Joe

[phily245]

It's still not working, gah!

I tried what you suggested, then I tried using another one I found on google and slightly modified:

<?php
if(!preg_match('/^(19|20)\d\d[-](0[1-9]|1[012])[-](0[1-9]|[12][0-9]|3[01])$/', $expiryDate) or !preg_match('/^(19|20)\d\d[-](0[1-9]|1[012])[-](0[1-9]|[12][0-9]|3[01])$/', $startDate)) {
	$issue = "9";
	return $issue;
}
?>

 

I need the - seperator so that I can use explode() on the date function. When I get this working with just a -, I'm going to add support for [- \/\.] and a switch statement for the explode.

[Pikachu2000]

Don't bother, it's an exercise in futility. Does the user intend for 03-08-2011 to be August 3 or march 8? There's no way to tell, and both will validate, which is why I suggested select fields.

[phily245]

It's meant to validate to 3rd August. We expect the user to enter it this way, as the end users are from the UK (like me) and we use dd-mm-yyyy. I also have an instruction to do it this way in the label on the field which the user enters the date into. I think a select statement will be overkill, as the dates needed can be from tomorrow to in multiple years time.

[joe92]

How is the date getting posted to the validation script? Can you give an example of how it looks just before it hits the preg_match.. i.e. after any html_entities etc. It may be a case of the anchors around your pattern messing things up for you.

 

If it helps, I have this uk date validation working on my site:

preg_match("~[0-9]{1,2}/[0-9]{1,2}/[0-9]{1,4}~", $startDate)

[phily245]

<?php echo $_POST["startDate"]; ?>

echos 20-11-2011 (if the date selected is the 20th November 2011)

[joe92]

It works for me. I just ran the following code:

<?php

$testing = '20-11-2011';

echo $testing.'<br/><br/>';

if(!preg_match('/^[\d]{2}-[\d]{2}-[\d]{4}$/', $testing)){
echo 'no match';
}
else{
echo 'match';
}
?>

 

And it displayed:

20-11-2011

match

 

Indicating that the regex works fine. The problem must lie elsewhere.

[phily245]

I had an extra i in $_POST["expiryDate"] when submitting the date. I just want to crawl away and hide in shame.