php 代码在 orderby 更改时创建新的 html 表

Question

我有一个简单的脚本，它使用 sql 查询从数据库中获取数据并按特定列排序信息。正如您在下面的查询中看到的那样，每次“层级”发生变化时，我都希望能够创建一个新的 html 表。我怎样才能将其分解，以便该层显示在新的附加 HTML 表中？下面获取并显示信息，但无法区分层级。关于如何格式化这个的任何想法？

<?php
    // You can place PHP like this

echo "<table class='table table-striped table-bordered table-hover table-condenced table-responsive'>";
echo "<tr><th>Channel</th><th>Description</th></tr>";

class TableRows extends RecursiveIteratorIterator { 
    function __construct($it) { 
        parent::__construct($it, self::LEAVES_ONLY); 
    }

    function current() {
        return "<td>" . parent::current(). "</td>";
    }

    function beginChildren() { 
        echo "<tr>"; 
    } 

    function endChildren() { 
        echo "</tr>" . "\n";
    } 
} 

$servername = "localhost";
$username = "test";
$password = "pass";
$dbname = "Channel_Lineup";

try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    $stmt = $conn->prepare("SELECT channel, description FROM Channel_LineUps WHERE Market_ID = 1 ORDER BY Tier ASC"); 
    $stmt->execute();

    // set the resulting array to associative
    $result = $stmt->setFetchMode(PDO::FETCH_ASSOC); 
    foreach(new TableRows(new RecursiveArrayIterator($stmt->fetchAll())) as $k=>$v) { 
        echo $v;
    }
}
catch(PDOException $e) {
    echo "Error: " . $e->getMessage();
}
$conn = null;
echo "</table>";    

?>

Answer 1

您的 SQL 语句没有返回层，因此很难打开它。

如果您更改返回层级的请求(将层级放在首位会使事情变得更简单):

$stmt = $conn->prepare("SELECT tier, channel, description FROM Channel_LineUps WHERE Market_ID = 1 ORDER BY Tier ASC");

然后你可以在 TableRows 类中添加一个 lastTier 值，如果当前层是和上次看到的不一样。您还可以更改 current() 函数以不输出“层”。

class TableRows extends RecursiveIteratorIterator {
    private $lastTier = NULL;

    function __construct($it) {
        parent::__construct($it, self::LEAVES_ONLY);
    }

    function current() {
        if (parent::key() != "tier") return "<td>" . parent::current(). "</td>";
    }

    function beginChildren() {
        if ($this->lastTier != parent::current()) {
            if (!is_null($this->lastTier)) echo "</table>\n";
            echo "<table class='table table-striped table-bordered table-hover table-condenced table-responsive'>\n";
            $this->lastTier = parent::current();
        }
        echo "<tr>";
    }

    function endChildren() {
        echo "</tr>" . "\n";
    }
}