比较PHP三个数组的值？

Question

I have a maybe stupid question?

I have three arrays. And I want to get different values from the first and third array. I created the following code but the returned values are wrong.

function ec($str){
    echo $str.'<br>';
}

$arr1 = array( array(
                    'letter' => 'A',
                    'number' => '1'
                ),

               array(
                    'letter' => 'B',
                    'number' => '2'
                ),

               array(
                    'letter' => 'C',
                    'number' => '3'
                )

    );

$arr2 = array( array(
                    'letter' => 'A',
                    'number' => '1'
                ),

               array(
                    'letter' => 'B',
                    'number' => '2'
                )

    );



 $arr3 = array( array(
                    'letter' => 'D',
                    'number' => '4'
                ),

               array(
                    'letter' => 'E',
                    'number' => '5'
                )

    );

    $mergeArr = array_merge($arr1,$arr3);
    foreach ($mergeArr as $kMerge => $vMerge){
        foreach ($arr2 as $val2){
            if($val2['letter'] != $mergeArr[$kMerge]['letter']){
                ec($mergeArr[$kMerge]['letter']);
            }
        }
    }

The result of this code is:

A
B
C
C
D
D
E
E

The result I want:

    C
    D
    E

Thanks in advance.

Answer 1

Based on the result you are looking for, this should do it:

$mergeArr = array_merge($arr1,$arr3);

$res = array_diff_assoc($mergeArr, $arr2);

var_dump($res);

See the snippet on codepad.