json_encode 输出对象而不是某些元素的数组

我有这个数组，我想将其编码为 json..

Array
    [0] => Array
        [0] => . Hour
        [1] => bteam_pvp
        [2] => crackpack
        [3] => tppi
        [4] => agrarian_plus
        [5] => agrarian2
        [6] => bteam_pve
        [7] => agrarian
        [8] => horizons
        [9] => m_lobby
        [10] => m_north
        [11] => m_south
        [12] => m_east
        [13] => hub
    [1] => Array
        [0] => 24
        [1] => 91
        [2] => 81
        [3] => 64
        [4] => 98
        [5] => 72
        [6] => 37
        [8] => 63
        [9] => 93
        [10] => 59
        [11] => 92
        [12] => 67
        [13] => 98

所以我用这个：

echo '[';
foreach ($data as $row) {
    echo json_encode($row) . ",";
}
echo ']';

我得到这个结果：

[
    [". Hour","bteam_pvp","crackpack","tppi","agrarian_plus","agrarian2","bteam_pve","agrarian","horizons","m_lobby","m_north","m_south","m_east","hub"],
    {"0":24,"1":94,"2":96,"4":98,"5":82,"6":69,"8":97,"9":98,"10":96,"11":98,"12":97,"13":99}
]

你能解释一下为什么最后一个元素被编码为对象而不是数组吗？

为了被编码为数组文字而不是对象，数组must是一个非稀疏的索引数组。

在你的情况下，你的最后一个数组丢失了[7]，使其稀疏，因此编码为对象。