Count the Numbers from a field in a web form

[foochuck]

I have a basic text input field on a web form.

 

I want to have my users type in 16 numbers ( it can be any sixteen numbers - as long as the count is 16 numbers exactly - I'm not checking it with a database )

 

Using a post method, the page submits the form to itself.

 

Basically, I'm just wondering how I can tell if 16 numbers have been entered into my field?

 

The field is named fm_id. I'm taking it from the $_POST and creating a variable called $id

 

How can I count the number of numbers in $id ?

 

Thanks

 

FOO

[Mchl]

You can use explode() to convert this string into an array, and then check how many values are there in the resulting array.

[Maq]

You could use a regular expression preg_all_match(); to find all single digit numbers.  I think there's a parameter that keeps track of the count.  Although, there may be an easier way with javascript...

[Psycho]

if (ctype_digit($input) && strlen($input)==16)
{
 echo "The input is numeric and is 16 characters long";
}
else
{
 echo "The input is not numeric and/or is not 16 characters long";
}

[foochuck]

Thanks mjdamato - that did the trick.

 

if (ctype_digit($input) && strlen($input)==16)
{
 echo "The input is numeric and is 16 characters long";
}
else
{
 echo "The input is not numeric and/or is not 16 characters long";
}

[jmurch]

Foo,

 

Have you tried JS.  You can give the users immediate feedback instead of waiting to post to the server for the check.

 

Jeff

 

[Maq]

Thanks mjdamato - that did the trick.

 

This problem has been solved already.

[Mchl]

Oh... you meant 16 digits not 16 numbers...

[Maq]

No, I think he meant numbers.

[Mchl]

mjdamato's solution works for digits

[Maq]

Yeah sorry  :-X  I looked at his solution and thought he checked for numerics...

[Psycho]

Have you tried JS.  You can give the users immediate feedback instead of waiting to post to the server for the check.

 

Javascript IS a great way to give the user immediate feedback, however it should NOT be relied upon as the only validation. You must ALWAYS have server-side validation. User can have JS turned off or submit data without using your form.

[foochuck]

Good point mj. Thanks again.

 

Have you tried JS.  You can give the users immediate feedback instead of waiting to post to the server for the check.

 

Javascript IS a great way to give the user immediate feedback, however it should NOT be relied upon as the only validation. You must ALWAYS have server-side validation. User can have JS turned off or submit data without using your form.