<div> 内容应在没有数据可从数据库检索时显示文本“数据为空”答案

【问题标题】：<div> content should display text "Data is empty" when there is no data to retrieve from database<div> 内容应在没有数据可从数据库检索时显示文本“数据为空”
【发布时间】：2019-09-05 01:50:34
【问题描述】：

根据我的问题，当没有要从数据库检索的数据时，我想用文本（数据为空）显示 div (id = "content") 的内容。我所知道的是使用javascript。但我在这种编程技能方面还是新手。谁能帮帮我？

下面是我的代码

<div class="row" id = "content">
    <div class="col-lg-12 grid-margin stretch-card">
        <div class="card bg-light">
            <div class="card-body double" style="height: 400px; overflow-y: scroll;">
                <h4 class="card-title">All Booking</h4>
                <table class="table table-bordered" >
                    <thead>
                    <tr>
                        <th>#</th>
                        <th>Requester</th>
                        <th>Factory</th>
                        <th>Room</th>
                        <th>Purpose</th>
                        <th>Status</th>
                        <th>Action</th>
                    </tr>
                    </thead>
                    <tbody >
                    <?php

                    $query = $conn->query("SELECT * FROM booking LEFT JOIN room ON booking.Room_ID = room.Room_ID WHERE Admin_email = '$Email' AND EndTime > GETDATE() ORDER BY booking.Book_No DESC");
                    while($row = $query->fetch(PDO::FETCH_ASSOC)){
                        $status=$row['Book_Status'];
                        if($status=="Approve")
                        {
                            $color="color:green";
                        }
                        else if($status=="Pending")
                        {
                            $color="color:blue";

                        }
                        else
                        {
                            $color="color:red";
                        }
                        echo "<tr>";
                        echo "<td>" . $row['Book_No'] . "</td>";
                        echo "<td>" . $row['Requested_by'] . "</td>";
                        echo "<td>" . $row['Fac_ID'] . "</td>";
                        echo "<td>" . $row['Room_Desc'] . "</td>";
                        echo "<td>" . $row['Meeting_Description'] . "</td>";
                        echo "<td style='$color'><strong>" . $status ."</strong></td>";
                        echo "<td>";
                        echo "<a class='btn btn-primary btn-block' href='../view_booking/view_booking.php?Book_No=". $row['Book_No'] ."' title='View Booking' data-toggle='tooltip'>View</a>";
                        echo "</td>";
                        echo "</tr>";
                    }
                    ?>
                    </tbody>
                </table><br>
            </div>
        </div>
    </div>
</div>

【问题讨论】：

您使用什么驱动程序连接到 MS SQL Server？

标签： javascript php sql-server

【解决方案1】：

您可以根据您的 SQL 查询将 <div> 标记包装在条件中。

例子：

$query = $conn->query("SELECT * FROM booking LEFT JOIN room ON booking.Room_ID = room.Room_ID WHERE Admin_email = '$Email' AND EndTime > GETDATE() ORDER BY booking.Book_No DESC");

$count = mysqli_num_rows($query); // if your query doesn't returns any error.

if($count > 0) { ?>

<div id=content> your all contents here </div>

<?php } else { ?>

<div id="content"> Data is empty </div>

<?php } ?>

【讨论】：