php将文件从文件插入到数组中

Question

我有一个带有城市和人口的文本文件以及一个PHP程序，该文件应读取文本文件并将文本插入数组，同时考虑到城市应该是关键，并且人口是数组的价值，并且该程序必须对数组按值并以表格式打印其键和值。

示例数据：

Tokyo   39105000
Jakarta 35362000
Delhi   31870000
Manila  23971000
Sao Paulo   22495000
Seoul   22394000
Mumbai  22186000
Shanghai    22118000
Mexico City 21505000
Guangzhou   21489000

这是代码：

    <?php
    $fileHandler = fopen("Info_array.txt", "rb");
    $data = [];

    while (!feof($fileHandler) ) {
        // read file row
        $row = fgets($fileHandler);

        $index = count($data);

        // explode array by space
        $data[$index] = explode(' ', $row);

        // explode data[$index][0] by '.', then insert into array in index 0 & 1
        array_splice($data[$index], 0, 1, explode('.', $data[$index][0]));
    }

    // sort array by array index 1
    usort($data, function ($prev, $next) {
        if ($prev[1] == $next[1]) {
            return 0;
        }

        return ($prev[1] < $next[1]) ? -1 : 1;
    });

    fclose($fileHandler);
?>

<table class="heavyTable">
    <thead>
        <tr>
            <th>City</th>
            <th>Population</th>
        </tr>
    </thead>
    <tbody>
        <?php foreach ($data as $item): ?>
            <tr>
                <td><?= $item[0] . '.' . $item[1] ?></td>
                <td><?= $item[2] ?></td>
                <td><?= $item[1] ?></td>
            </tr>
        <?php endforeach; ?>
    </tbody>
  </table>

我当前会遇到错误：

Warning: Undefined array key 1 in C:\xampp\htdocs\phpexercise.php on line 20

Warning: Undefined array key 1 in C:\xampp\htdocs\phpexercise.php on line 20

Warning: Undefined array key 1 in C:\xampp\htdocs\phpexercise.php on line 20

Warning: Undefined array key 1 in C:\xampp\htdocs\phpexercise.php on line 20

关于如何执行此操作的任何建议将不胜感激，我现在​​几天都在挣扎。

Answer 1

发布解决方案：

<?php
 $fileHandler = fopen("Info_array.txt", "rb");
 $data = array();

 while (!feof($fileHandler) ) {
 // read file row
 $row = fgets($fileHandler);

 // explode array by tab
 $temp = explode('\t', $row);
 $data += [$temp[0] => $temp[1]];
 //array_push($data, $temp[0], $temp[1]);
 }

 fclose($fileHandler);

 arsort($data);
?>
<table class="heavyTable">
    <thead>
        <tr>
            <th>City</th>
            <th>Population</th>
        </tr>
    </thead>
    <tbody>
<?php foreach( $data as $city => $pop): ?>
<tr>
<td><?= $city ?></td>
<td><?= $pop ?></td>
</tr>
<?php endforeach; ?>
   </tbody>
  </table>