求助：关于php一段简单代码

Question

这是php和mysql web开发书中一个例子，目的就是把文件保存的订单信息炸开，用表格显示。我运行时为什么只显示表头，没有表格数据呢。
orders.txt中就是订单信息，用Tab分隔的，已正确读取到$orders中。貌似是后边的for循环中有问题。

Bob's Auto Parts - Customer Orders

Bob's Auto Parts

Customer Orders

<?php
//Read the entire file
//Each order becomes an element in the array
$orders = file("./orders.txt");

//count the number of orders in the array
$number_of_orders = count($orders);

if($number_of_orders = 0) {
    echo "<p><strong>No orders pending. Please try again later.</strong></p>";
}

echo "<table border=\"1\">\n";
echo "<tr><th bgcolor=\"#CCCCFF\">Order Date</th>
          <th bgcolor=\"#CCCCFF\">Tires</th>
          <th bgcolor=\"#CCCCFF\">Oil</th>
          <th bgcolor=\"#CCCCFF\">Spark plugs</th>
          <th bgcolor=\"#CCCCFF\">Total</th>
          <th bgcolor=\"#CCCCFF\">Address</th>
      </tr>";
for($i = 0; $i < $number_of_orders; $i++) {
    //Split up each line
    $line = explode("\t", $orders[$i]);


    //keep only the number of items ordered
    $line[1] = intval($line[1]);
    $line[2] = intval($line[2]);
    $line[3] = intval($line[3]);

    //output each other 
    echo "<tr>
            <td>".$line[0]."</td>
            <td align=\"right\">".$line[1]."</td>
            <td align=\"right\">".$line[2]."</td>
            <td align=\"right\">".$line[3]."</td>
            <td align=\"right\">".$line[4]."</td>
            <td>".$line[5]."</td>
          </tr>";
}

echo "</table>";

?>

Answer 1

看上去没问题 把那个txt文件贴下看看