PHP - Is there a way to verify all values in an array - php

Question

Using PHP..
Here is what I have.. I'm gonna explain the whole thing and maybe someone can help me with the logic and maybe point me in the right direction.
I have a mail system I am working on. In the cc part, I am allowing the user to seperate the values by a semicolon, like so: 1;2;3;4...
When these values are passed to my function, I am using explode to get them into an array. What I want to do is some checking first. I want to firstly make certain that the format is correct and that every value is correctly seperated. If not, I should show an error. Once this is done, I want to make certain that every number is actually valid. I can query the database, put the reslts into an array and was thinking to use the in_array() function to verify this but I'm not certain that it will work. Can someone please help me out with the best way to handle this?
Thanks.
EDIT:
What is the best way to detect a bogus value in the CSV list of values?

Answer 1

In order to verify that each number was correct seperated, you want to check that there is no whitespace in the answer. So something like this should work:
$text = trim($id);
if(strpos(" ", $id) !== false)
{
//error
}
Next, to check for the values, it is very simple
if(!in_array($id, $database_ids))
{
// error
}
Finally, if you are only using numeric values, check that the id is numeric
if(!is_numeric($id))
{
//error
}
To combine, wrap it into an array
foreach($exploded_array as $key => $id)
{
$id = trim(id);
if(!is_numeric($id))
{
//error
}
if(strpos(" ", $id) !== false)
{
//error
}
if(!in_array($id, $database_ids))
{
// error
}
}
I hope the code was pretty self explanatory where it got the variables, but if you need me to explain more, feel free to ask.

Answer 2

You are looking for something like:
foreach ($array as $value) {
//do checking here
}

Answer 3

array_filter could be an option.

Answer 4

As whichdan suggested, here is an implementation that relies on array_filter():
<?php
function checkValue($value)
{
$id = trim(id);
if(!is_numeric($id))
{
return false;
}
if(strpos(" ", $id) !== false)
{
return false;
}
if(!in_array($id, $database_ids))
{
return false;
}
return true;
}
$values = '1;2;3;4';
$values_extracted = explode(';', $values);
if(count($values) == count(array_filter($values_extracted), 'checkValue'))
{
// Input was successfully validated
}
?>