我想在數組的一個鍵中包含多個鍵。我嘗試了以下語法：<?phpfor($i = 0 ; $i < 3 ; $i++){    $str = 'name'.$i;    if ($i == 0){        $date = 'today';    }    elseif ($i == 1){        $date = 'yesterday';    }    else{        $date = 'tomorrow';    }    if ($date == "yesterday"){        $arr[] = ["user" => $str, "time" => '2020-10-2'];    }    elseif ($date == "today"){        $arr[] = ["user" => $str, "time" => '2020-10-3'];    }    elseif ($date == "tomorrow"){        $arr[] = ["user" => $str, "time" => '2020-10-4'];    }}print_r($arr);但結果數組似乎只有一個元素。Array(    [0] => Array        (            [user] => name1            [time] => 2020-10-2        ))我不知道發生了什么事。感謝幫助。更新： 我分享這個是因為上面的代碼顯然沒有顯示我遇到的問題。這是實際的代碼：<?php$txt_file = fopen('path.txt', 'r');$date = strtotime(fgets($txt_file));$arr = [];for($i = 0 ; !feof($txt_file) ; $i++){    $str = explode(':', fgets($txt_file));    if (count($str) != 2){        continue;    }    if ($str[1] == "yesterday"){        $arr[] = ["user" => $str[0], "time" => date("Y-m-d", $date-3600*24)];    }    elseif ($str[1] == "today"){        $arr[] = ["user" => $str[0], "time" => date("Y-m-d", $date)];    }    elseif ($str[1] == "tomorrow"){        $arr[] = ["user" => $str[0], "time" => date("Y-m-d", $date+3600*24)];    }}file_put_contents("INFO.json", json_encode($arr));fclose($txt_file);路徑.txt 包含：3 October 2005quera1:todayquera2:tomorrowquera3:yesterdayquera4:today最終的 INFO.json 文件是：[{"user":"quera4","time":"2005-10-03"}]它只有最后一個元素。