1：DBHelper.class.php
<?php
class DBHelper{
private $mysqli;
private static $host='127.0.0.1';
private static $user='root';
private static $pwd='mysql';
private static $dbname='test'; //通过构造方法进行初始化操作
public function __construct(){
$this->mysqli=new mysqli(self::$host,self::$user,self::$pwd,self::$dbname)
or die('数据库链接出错:'.$this->mysqli->connect_error);
//设置数据库编码为utf8
$this->mysqli->query('set names utf8');
} //执行查询语句
public function execute_dml($sql){
$arr=array();
$result=$this->mysqli->query($sql) or die($this->mysqli->error);
if($result){
while($row=$result->fetch_assoc()){
//将查询结果封装到一个数组中，返回给方法调用处
$arr[]=$row;
}
//释放查询结果资源
$result->free();
}
return $arr;
} //执行增加、删除、更新语句
public function execute_dql($sql){
$result=$this->mysqli->query($sql) or die($this->mysqli->error);
if(!$result){
return 0;//表示操作失败
}else{
if($this->mysqli->affected_rows>0){
return 1;//操作成功
}else{
return 2;//没有受影响的行
}
}
}
}
?>
2:使用案例index.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<?php
require_once('DBHelper.class.php');
$dbhelper=new DBHelper();
$sql='select id,name,age from user';
$users=$dbhelper->execute_dml($sql);
if(!empty($users)){
?>
<table style="width:80%;">
<tr>
<th>ID</th>
<th>Name</th>
<th>Age</th>
<th>操作</th>
</tr>
<?php
foreach($users as $user){
?>
<tr align='center'>
<td><?php echo $user['id'];?></td>
<td><?php echo $user['name'];?></td>
<td><?php echo $user['age'];?></td>
<td>
<a href="delete.php?id=<?php echo $user['id'];?>">Delete</a> |
<a href="show.php?id=<?php echo $user['id'];?>">Show</a>
</td>
</tr>
<?php }?>
</table>
<?php
}else{
echo '<h1>No result!</h1>';
}
?>
<hr/>
<a href="add.php" style="font-size:24px;font-weight:bold;">Add a new user</a>
</body>
</html>