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PHP array_uintersect() Function

Definition and Usage

The array_uintersect() 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, 0 if the returned array should contain this element.

Syntax

array_uintersect(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;
  }
if ($v1 > $v2) return 1;
  {
  return -1;
  }
return 1;
}
$a1=array("a"=>"Cat","b"=>"Dog","c"=>"Horse");
$a2=array(1=>"Cat",2=>"Dog",3=>"Fish");
print_r(array_uintersect($a1,$a2,"myfunction"));
?>

The output of the code above will be:

Array ( [a] => Cat [b] => Dog )

Complete PHP Array Reference