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PHP array_udiff_uassoc() Function

Definition and Usage

The array_udiff_uassoc() function compares two or more arrays, in two user-made functions, and returns an array containing the elements from the first array, if the user-made functions allow it. The first user-made function compares array keys, and the second compares array values, and both 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_uassoc(array1,array2,array3...,function1,function2)

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
function1	Required. The name of the user-made function that compares the array keys
function2	Required. The name of the user-made function that compares the array values

Tips and Notes

Tip: You can compare the first array with one array, or as many as you like.

Note: For comparison, the key is used in the first function and the value is used in the second. They are both user-made functions.

Example

<?php
function myfunction_key($v1,$v2) 
{
if ($v1===$v2)
	{
	return 0;
	}
return 1;
}

function myfunction_value($v1,$v2) 
{
if ($v1===$v2)
	{
	return 0;
	}
return 1;
}
$a1=array("a"=>"Cat","b"=>"Dog","c"=>"Horse");
$a2=array("a"=>"Cat","b"=>"Dog","c"=>"Fish");
print_r(array_udiff_uassoc($a1,$a2,"myfunction_key","myfunction_value"));
?>

The output of the code above will be:

Array ( [c] => Horse )

Complete PHP Array Reference