Question

我在3周前开始进行网络开发。今天我遇到了这个问题，只有第一次（$ query-＆gt; fetch（））有效，第二次没有。

我四处搜索，我应该使用$ rows数组，但我想我实现错误，因为它没有工作。

<div class="container-fluid">
            <div class="row">

                <aside class="sidebar col-md-3 col-md-offset-1 col-md-push-8">


                    <div class="widget">
                        <h2>Recent Posts</h2>

                        <ul>
                            <?php while($query->fetch()): ?>

                            <li><?php echo "<a href='post.php?
 id=$post_id'>$title</a>" ?></li>

                            <?php endwhile ?>

                        </ul>
                    </div>


                </aside>



                <div class="col-md-8 posts col-md-pull-4">
                    <div class="row">

                        <?php 
                            while($query->fetch()):
                            $lastspace = strrpos($content, ' ');
                            ?>


                            <article class="post-excerpt">

                                <div class="col-md-6 post">
                                    <a href="#">
                                        <img src="../img/blog_posts/<?php echo $image ?>" class="img-responsive">
                                    </a>
                                <header>
                                    <a href="#">
                                        <h3><?php echo $title ?></h3>
                                    </a>
                                    <p class="post-meta">
                                        <?php echo $category ?>
                                        <span><?php echo $date ?></span>
                                    </p>
                                </header>
                                <p>
                                    <?php echo substr($content, 0, $lastspace)."<a href='post.php?id=$post_id'> ..Read More</a>" ?>
                                </p>

                                </article>

                                <?php endwhile ?>

                                </div>
                    </div>

                            <?php 
                                if($prev > 0){
                                    echo "<a href='blog.php?p=$prev'>Prev</a>";
                                }
                                if($page < $pages){
                                    echo "<a href='blog.php?p=$next'>Next</a>";
                                }
                            ?>
                </div>
            </div>
        </div>

查询：

$query = $db->prepare("SELECT id, title, date, image, LEFT(content,500) AS content, category FROM blog INNER JOIN categories ON categories.category_id=blog.category_id order by id desc limit $start, $per_page");
$query->execute();
$query->bind_result($post_id, $title, $date, $image, $content, $category);

Answer 1

如果要从结果集中提取数据两次意味着您需要在第二个while循环之前使用$query->data_seek(0);将内部数据指针重置为0。否则你会收到错误。

更新1：在第二次循环之前使用此

$query->data_seek(0);

Answer 2

我通过在第一个循环中使用数组然后在for循环中回显它来解决它，其中第二个while循环是。

<div class="container-fluid">
<div class="row">
    <div class="col-md-8 posts">
                <div class="row">

                    <?php 
                        while($query->fetch()):
                        $lastspace = strrpos($content, ' ');
                        $link[] = "<li><a href='post.php?id=$post_id'>$title</a></li>";
                    ?>

                    <article class="post-excerpt">

                            <div class="col-md-6 post">
                                <a href="#">
                                    <img src="../img/blog_posts/<?php echo $image ?>" class="img-responsive">
                                </a>
                                <header>
                                    <a href="#">
                                        <h3><?php echo $title ?></h3>
                                    </a>
                                    <p class="post-meta">

                                    <?php echo $category ?>
                                    <span><?php echo $date ?></span>

                                    </p>
                                </header>
                                <p>

                                <?php echo substr($content, 0, $lastspace)."<a href='post.php?id=$post_id'> ..Read More</a>" ?>

                                </p>
                            </div> 
                    </article>

                    <?php endwhile ?>

                </div>

        <div class="col-md-6 pagination">
           <?php 

             if($prev > 0){
                echo "<a href='blog.php?p=$prev' id='previous'>Prev</a>";
              }
              if($page < $pages){
                echo "<a href='blog.php?p=$next' id='next'>Next</a>";
              }

            ?>
        </div>

    </div>              

    <aside class="sidebar col-md-3">
        <div class="widget">
        <h2>About me</h2>
        <p>
            I'm Yousef. Aspiring web, mobile, and soon-to-be game developer. Well I'm also a geek, a nerd, and I love comic books and comic book accesories. One day I will make the world's coolest website.
        </p>
        </div>

        <div class="widget">
            <h2>Recent Posts</h2>
            <ul>
                <?php 

                for ($x = 0; $x <= 2; $x++) {
                    echo $link[$x];
                }

                ?>
            </ul>
        </div>
    </aside>
</div>

虽然（$ query-＆gt; fetch（））两次

2 个答案: