array_diff() Function meaning:
array_diff() function returns the difference array of two arrays. This array contains all keys that are in the array being compared, but are not in any of the other parameter arrays. In the returned array, the key names remain unchanged.
For example:
<!DOCTYPE html> <html> <body><?php $a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow"); $a2=array("e"=>"red","f"=>"green","g"=>"blue"); $result=array_diff($a1,$a2); print_r($result); ?></body> </html>
Run result:
Array ( [d] => yellow )
Syntax:
##array_diff(array1,array2,array3.. .);Parameter explanation:
array1 Required. The first array to compare with other arrays. array2 Required. The array to compare to the first array. array3,... Optional. Additional array to compare with the first array.Tips and Notes
Tips: One or more arrays can be compared with the first array. Note: Only values are used for comparison. Return value: Returns the difference array, which includes all key values that are in the compared array (array1) but are not in any other parameter array (array2 or array3, etc.).<!DOCTYPE html> <html> <body><?php $a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow"); $a2=array("e"=>"red","f"=>"black","g"=>"purple"); $a3=array("a"=>"red","b"=>"black","h"=>"yellow"); $result=array_diff($a1,$a2,$a3); print_r($result); ?></body> </html>
Array ( [b] => green [c] => blue )
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