Proper Date Checking on a form

[TapeGun007]

I'm just curious if there's a much better way to do this:

 

I have a form and the input looks like this:

 

<td><input name="InspectionExp" value="<?=$InspectionExp; ?>" id="date4" placeholder="mm-dd-yyyy" /></td>

 

The id on the form is for a jquery that auto formats the input field when selected to "__-__-____".

 

By default a new user InspectionExp is a DATE field in mySQL and is set to NULL.

 

So when the form is initially loaded up, the INPUT field above is blank with the place holder showing.

 

So first I check

 

 

if(isset($_POST['LicenseExp']) {
 

 

Then for whatever reason this seems to be the only thing that works right, but seems really sloppy to me:

 

 

if(!strlen($LicenseExp) == 10){ $LicenseExp = DateTime::createFromFormat('m-d-Y', $_POST['LicenseExp'])->format('Y-m-d'); }

 

If I don't have an IF statement, then by default it's going to UPDATE the database with a 1969-12-31 date on new users.  I can't use isset because the form makes the value set (again only on new users).

 

I mean, the code works yes, but I am pretty certain one of you gurus could show me a better way.

 

 

[TapeGun007]

Whoops... I thought it worked. but when submitting the form with nothing in the INPUT field it crashes on the

if(!strlen($PostLicenseExp) == 10){ echo "yes"; $PostLicenseExp = DateTime::createFromFormat('m-d-Y', $_POST['LicenseExp'])->format('Y-m-d'); }

I see... I didn't need the ! before strlen...I had it the wrong way around.

Edited January 20, 2017 by TapeGun007

[Jacques1]

So is the field required or not? If it is required, then it should actually say that.

 

You need three checks:

• If the parameter is present at all. isset() does this.
• If the date is formally valid. The DateTime::createFromFormat() method does this, but you must check the return value. Don't assume that your jQuery stuff will prevent all input errors.
• If the date is plausible.

In any case, I strongly recommend you use a date picker instead of making the user enter a bunch of digits. It will greatly increase usability und reduce the amount of garbage input.