Definition and Usage
The array_udiff() function compares two or more arrays, in a user-made function, and returns an array containing the elements from the first array, if the user-made function allows it. The user-made function compares array values, and returns a numeric value, a positive number (1) if the returned array should contain this element, and 0, or a negative number (-1), if not.Syntax
array_udiff(array1,array2,array3...,function)
| Parameter | Description |
|---|---|
| array1 | Required. The first array is the array that the others will be compared with |
| array2 | Required. An array to be compared with the first array |
| array3 | Optional. An array to be compared with the first array |
| function | Required. The name of the user-made function |
Tips and Notes
Tip: You can compare the first array with one array, or as many as you like.Note: Only the value is used in the comparison.
Example
<?php
function myfunction($v1,$v2)
{
if ($v1===$v2)
{
return 0;
}
return 1;
}
$a1=array("a"=>"Cat","b"=>"Dog","c"=>"Horse");
$a2=array(1=>"Cat",2=>"Dog",3=>"Fish");
print_r(array_udiff($a1,$a2,"myfunction"));
?>
function myfunction($v1,$v2)
{
if ($v1===$v2)
{
return 0;
}
return 1;
}
$a1=array("a"=>"Cat","b"=>"Dog","c"=>"Horse");
$a2=array(1=>"Cat",2=>"Dog",3=>"Fish");
print_r(array_udiff($a1,$a2,"myfunction"));
?>
Array ( [c] => Horse )