如何在PHP中巧妙地停止“ while循环”？

Question

我在创建代码时遇到麻烦，该代码回显了对应于mysql数据库行的一堆东西。 它需要继续创建内容，直到使用完所有行，然后停止。

当前存在的行数为5

但是由于某种原因，php文件会导致浏览器继续加载（永远不会结束）。 任何帮助，将不胜感激！ 谢谢！

问题不在此PHP文件中，而在我的HTML代码中，谢谢大家的帮助

<?php 

mysql_connect ("localhost", "root", "") or die ("We couldn't connect!");
mysql_select_db ("dr");
mysql_query ("SELECT * FROM songs");
$result = mysql_query ("SELECT * FROM songs");

while ($row=mysql_fetch_array($result)) {

    $name = $row ['songname'];
    $genres = $row ['songgenres'];
    $mediafire = $row ['mediafirelink'];
    $dropbox = $row ['dropboxlink'];
    $source = $row ['audiosource'];

    echo "
    <div class='playing'>
            <!-- ======== Song Name ======== -->
                <li class='songnameli' id='$source'>
                    <span class='info'>$name</span>
                    <audio>
                        <source src='music/singles/$source.mp3'>
                        <source src='music/singles/$source.ogg'>
                    </audio>
                </li>

            <!-- ======== Playlist ======== -->
                <li class='playlistli'>
                    <img src='icons/addtoplaylist.png' title='Add tot the playlist!' />
                </li>

            <!-- ======== Genres ======== -->
                <li class='genresli'>
                    <img src='icons/genres.png' title='Related genres' />
                    <span class='addedtext genres'>$genres</span>
                </li>

            <!-- ======== Social Media links ======== -->
                <li>
                    <span>
                    <img src='icons/share.png' alt='Share this with your friends!' title='Share this!'>
                    <!-- /// facebook /// -->
                        <a href='http://www.facebook.com/sharer.php?u=http://www.declassified-recordings.com'
                           class='addedtext nlink'
                           target='blank_'
                           onclick='popup (this.href, 800, 500); return false'>Facebook
                        </a>

                    <span>/</span>

                    <!-- /// Twitter /// -->
                        <a href='http://twitter.com/share?
                            text=Thank%20you%20For%20Sharing!%20It%20means%20the%20world%20to%20us!%40Declassifi3d%20
                            &url=http://www.declassified-recordings.com'
                           class='twitterlink nlink'
                           target='blank_'
                           onclick='popup (this.href, 800, 500); return false'>Twitter</a>


                    </span>

                </li>

            <!-- ======== Download links ======== -->

                <li>
                    <img src='icons/download.png' title='Download!'  />
                    <span>
                        <!-- /// Mediafire /// -->
                            <a href='$mediafire'
                               class='addedtext nlink'
                               target='_blank'>Mediafire</a>

                        <span class='genres'>/</span>

                        <!-- /// Dropbox /// -->
                            <a href='$mediafire'
                               class='twitterlink nlink'
                               target='_blank'>Dropbox</a>


                    </span>
                </li>
    </div>";
}
mysql_close ();
?>

Answer 1

首先，为什么您要像下面这样将这两个mysql_query命令彼此相对：

mysql_query ("SELECT * FROM songs");
$result = mysql_query ("SELECT * FROM songs");

只要摆脱掉第一个，就可以将实际的SQL设置成这样的变量：

$query_sql = "SELECT * FROM songs";
$result = mysql_query ($query_sql);

但是针对该问题，请从此更改您的MySQL查询：

"SELECT * FROM songs"

要将LIMIT用作SELECT一部分：

LIMIT子句可用于约束SELECT语句返回的行数。 LIMIT接受一个或两个数字参数，这两个参数都必须是非负整数常量（使用预处理语句时除外）。

例如，像这样：

"SELECT * FROM songs LIMIT 0,50"

然后，您可以编写一些逻辑来处理分页，例如：

$start = 0;
$how_many = 50;
$query_sql = "SELECT * FROM songs LIMIT $start, $how_many";
$result = mysql_query ($query_sql);

Answer 2

我的第一个问题是桌子有多大？

如果是几千行，建议将其分页，一次仅加载50首歌曲。

如果只有几百个，则只需要服务器花费一些时间来处理数据。

另外，要不更正您的代码，但可能会有所帮助，请尝试以下操作：

<?
    $connection = mysqli_connect ("localhost", "root", "", "dr") or die ("We couldn't connect!");
    $result = mysqli_query($connection, "SELECT * FROM songs");
    while ($row=mysqli_fetch_array($result)) {

        $name = $row ['songname'];
        $genres = $row ['songgenres'];
        $mediafire = $row ['mediafirelink'];
        $dropbox = $row ['dropboxlink'];
        $source = $row ['audiosource'];

        echo "
        <div class='playing'>
                <!-- ======== Song Name ======== -->
                    <li class='songnameli' id='$source'>
                        <span class='info'>$name</span>
                        <audio>
                            <source src='music/singles/$source.mp3'>
                            <source src='music/singles/$source.ogg'>
                        </audio>
                    </li>

                <!-- ======== Playlist ======== -->
                    <li class='playlistli'>
                        <img src='icons/addtoplaylist.png' title='Add tot the playlist!' />
                    </li>

                <!-- ======== Genres ======== -->
                    <li class='genresli'>
                        <img src='icons/genres.png' title='Related genres' />
                        <span class='addedtext genres'>$genres</span>
                    </li>

                <!-- ======== Social Media links ======== -->
                    <li>
                        <span>
                        <img src='icons/share.png' alt='Share this with your friends!' title='Share this!'>
                        <!-- /// facebook /// -->
                            <a href='http://www.facebook.com/sharer.php?u=http://www.declassified-recordings.com'
                               class='addedtext nlink'
                               target='blank_'
                               onclick='popup (this.href, 800, 500); return false'>Facebook
                            </a>

                        <span>/</span>

                        <!-- /// Twitter /// -->
                            <a href='http://twitter.com/share?
                                text=Thank%20you%20For%20Sharing!%20It%20means%20the%20world%20to%20us!%40Declassifi3d%20
                                &url=http://www.declassified-recordings.com'
                               class='twitterlink nlink'
                               target='blank_'
                               onclick='popup (this.href, 800, 500); return false'>Twitter</a>


                        </span>

                    </li>

                <!-- ======== Download links ======== -->

                    <li>
                        <img src='icons/download.png' title='Download!'  />
                        <span>
                            <!-- /// Mediafire /// -->
                                <a href='$mediafire'
                                   class='addedtext nlink'
                                   target='_blank'>Mediafire</a>

                            <span class='genres'>/</span>

                            <!-- /// Dropbox /// -->
                                <a href='$mediafire'
                                   class='twitterlink nlink'
                                   target='_blank'>Dropbox</a>


                        </span>
                    </li>
        </div>";


    }




    mysqli_close($connection);

?>

我将不再使用mysql_connection和旧格式，它已经过时了，我将使用mysqli进行所有操作。 http://www.php.net//manual/en/book.mysqli.php

Answer 3

如果我是我，我将更改2件事，其中之一是@JakeGould建议之类的结果限制，并且我将更改您回显HTML代码的方式（这将使插入者更容易），如下所示：

您也忘记将您的<li>放在<ul>

<?php


while ($row=mysql_fetch_array($result)) {

$name = $row ['songname'];
$genres = $row ['songgenres'];
$mediafire = $row ['mediafirelink'];
$dropbox = $row ['dropboxlink'];
$source = $row ['audiosource'];

?>

<div class='playing'>
    <ul>>
        <!-- ======== Song Name ======== -->
            <li class='songnameli' id='$source'>
                <span class='info'><?php echo $name; ?></span>
                <audio>
                    <source src='music/singles/$source.mp3'>
                    <source src='music/singles/$source.ogg'>
                </audio>
            </li>

        <!-- ======== Playlist ======== -->
            <li class='playlistli'>
                <img src='icons/addtoplaylist.png' title='Add tot the playlist!' />
            </li>

        <!-- ======== Genres ======== -->
            <li class='genresli'>
                <img src='icons/genres.png' title='Related genres' />
                <span class='addedtext genres'><?php echo $genres; ?></span>
            </li>

        <!-- ======== Social Media links ======== -->
            <li>
                <span>
                <img src='icons/share.png' alt='Share this with your friends!' title='Share this!'>
                <!-- /// facebook /// -->
                    <a href='http://www.facebook.com/sharer.php?u=http://www.declassified-recordings.com'
                       class='addedtext nlink'
                       target='blank_'
                       onclick='popup (this.href, 800, 500); return false'>Facebook
                    </a>

                <span>/</span>

                <!-- /// Twitter /// -->
                    <a href='http://twitter.com/share?
                        text=Thank%20you%20For%20Sharing!%20It%20means%20the%20world%20to%20us!%40Declassifi3d%20
                        &url=http://www.declassified-recordings.com'
                       class='twitterlink nlink'
                       target='blank_'
                       onclick='popup (this.href, 800, 500); return false'>Twitter</a>


                </span>

            </li>

        <!-- ======== Download links ======== -->

            <li>
                <img src='icons/download.png' title='Download!'  />
                <span>
                    <!-- /// Mediafire /// -->
                        <a href='<?php echo $mediafire; ?>'
                           class='addedtext nlink'
                           target='_blank'>Mediafire</a>

                    <span class='genres'>/</span>

                    <!-- /// Dropbox /// -->
                        <a href='<?php echo $mediafire; ?>'
                           class='twitterlink nlink'
                           target='_blank'>Dropbox</a>


                </span>
            </li>
        </ul>
</div>