php - mysql php 的异常表输出

Question

为什么我会在表输出中得到这些额外的层？我需要从 table 上删除那些额外的层。我做错了什么？这里究竟发生了什么？更新了代码。

<?php
$con=mysqli_connect("localhost","root", "", "cop");

if (mysqli_connect_errno()){
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$sql= mysqli_query ($con, "SELECT FirstName, Practice FROM Members");

echo "
    <style>th {
    font: bold 11px 'Trebuchet MS', Verdana, Arial, Helvetica,
    sans-serif;
    color: #6D929B;
    border-right: 1px solid #C1DAD7;
    border-bottom: 1px solid #C1DAD7;
    border-top: 1px solid #C1DAD7;
    letter-spacing: 2px;
    text-transform: uppercase;
    text-align: left;
    padding: 6px 6px 6px 12px;
    background: #CAE8EA url(images/bg_header.jpg) no-repeat;
}

th.nobg {
    border-top: 0;
    border-left: 0;
    border-right: 1px solid #C1DAD7;
    background: none;
}</style>


<table border='1'>
<tr>
<th>FirstName</th>
<th>Practice</th>
</tr>";

while($row = mysqli_fetch_array($sql))
{
echo "<tr>";
echo "<td>" . $row['FirstName'] . "</td>";
echo "<td>" . $row['Practice'] . "</td>";
echo "</tr>";
}

echo "</table>";

Unusual Table output

Answer 1

如果您要做这样的事情，您将能够判断数据中是否存在空列值

while( $row = mysqli_fetch_array($sql) ){

    if( !empty( $row['FirstName'] ) && !empty( $row['Practice'] ) ){
        $firstname=$row['FirstName'];
        $practice=$row['Practice'];
    } else{
        $firstname=$practice='empty';
    }

    echo "
        <tr>
            <td>{$firstname}</td>
            <td>{$practice}</td>
        </tr>";

}

或者，如果已知该行包含值而不是空单元格，则仅输出该行

while( $row = mysqli_fetch_array($sql) ){

    if( !empty( $row['FirstName'] ) && !empty( $row['Practice'] ) ){
        $firstname=$row['FirstName'];
        $practice=$row['Practice'];
        echo "
            <tr>
                <td>{$firstname}</td>
                <td>{$practice}</td>
            </tr>";     
    }
}