在php中过滤数组中的特定列

I am trying to filter a specific column in an array in php using the code below:

(strpos( 'meeting',$event['categories'] ) == false )

It is not working actually. An example of what [categories] hold is:

$event['categories'] = 'meeting;skype'

Thanks in advance!

You need to flip the arguments to strpos():

if (strpos($event['categories'],  'meeting') === false) {
    echo $event['categories'] . ' does not contain "meeting"';
}

Also, use strict comparison (=== vs ==), as meeting could be at the start of the string, and then strpos() would return 0, which would evaluate to false (which would be wrong in that case).

For reference, see:

• http://php.net/manual/en/function.strpos.php

For an example, see:

• https://3v4l.org/Ab4ud

I think you should use === not == and also flip the arguments

(strpos($event['categories'] , 'meeting') === false )

strpos could return 0 or false and when you use == then zero is like false

see compression operators

see strpos() docs

<?php

$event = ['categories' => 'meeting;skype'];
$needle = 'meeting';
$haystack = $event['categories'];
if( ($pos = strpos( $haystack, $needle )) === false){
   echo "
$needle not found in $haystack";
} 
else
{
     echo "
$needle exists at position $pos in $haystack";
}

See demo

The two things to watch out for are the order of the parameters for strpos() as well as doing a strict comparison using the identity operator ("===") so that when the 'needle' appears at position zero of the 'haystack' it's not mistakenly deemed a false result which occurs if you use the equality operator ("=="), given that in PHP zero == false.