小弟正學習ajax中, 跟網上教學 做了以一下程序,
問題是在js 中的dataType: "html",
如我把它改成"json" 就會報錯了,
有大大可解答一下嗎? 如果想用json格式轉到 另一頁進行處理應該如何做?

謝謝

    <div id='adphp'></div>
    <?php
    $data_array_en = [
        "1" => "Apple",
        "2" => "HTC",
        "3" => "Samsung",
        "4" => "ASUS",
        "5" => "Sony"
    ];

    $data_json_en = json_encode($data_array_en);

    echo $data_json_en;
    ?>

    <script>

        var ar = <?php echo json_encode($data_array_en); ?>

        $.ajax({
            url: 'http_ajax.php',
            type: "POST",
            dataType: "html",
            data: ar,



            error: function() {
                alert('Ajax request 發生錯誤');
            },
            success: function(res) {
                alert('Ajax success!');
                console.log(res);
                document.getElementById('adphp').innerHTML = res
            }
        });
    </script>

http_ajax.php

<?php
$data = $_POST;

foreach ($data as $value) {

    echo $value."<br>";
  
  }
?>