php 用面向对象的方法对数据库增删改查

主页面
<body>
<h1>主页面</h1>
<table width="100%" border="1" cellpadding="0" cellspacing="0">
<tr>
    <td>代号</td>
    <td>姓名</td>
    <td>性别</td>
    <td>民族</td>
    <td>生日</td>
    <td>操作</td>
</tr>
<?php
//造对象
$db = new MySQLi("localhost","root","123","mydb");
//判断是否出错
!mysqli_connect_error() or die("连接失败！");
//写SQL语句
$sql = "select * from Info";
//执行SQL语句
$result = $db->query($sql);

//读取数据
$attr = $result->fetch_all();

//遍历数组，显示
foreach($attr as $v)
{
    
    $sex = $v[2]?"男":"女";
    
    $sql = "select Name from Nation where Code = '{$v[3]}'";
    $r = $db->query($sql);
    $a = $r->fetch_row();
    
    echo "
    <tr>
    <td>{$v[0]}</td>
    <td>{$v[1]}</td>
    <td>{$sex}</td>
    <td>{$a[0]}</td>
    <td>{$v[4]}</td>
    <td><a href='delete.php?code={$v[0]}'>删除</a><a href='update.php?code={$v[0]}'>修改</a></td>
</tr>
    ";
}
?>
</table>
<a href="add.php">添加数据</a>
</body>
View Code