玩一下php的pdo操作
pdo模块，实际是php data object php数据对象
默认php.ini里面是开着的
首先php用来操作数据库的一共有3大类
- pdo类
- 预处理类
- 异常处理类
在写一个简单小模块中先熟悉一下pdo类下面的这些操作方法
- 连接pdo数据库
//dsn 数据源名称
$dsn ="mysql:host=localhost;dbname=www.hm.com";
//数据库名称
$username = "hmcom";
//数据库密码
$password = "123456";
//pdo对象
$pdo = new PDO($dsn,$username,$password);
//设置字符集
//exec()执行一条sql 并返回条数，用于增删改 查用query()
$pdo->exec('set names utf8');
//设置属性
$pdo->setAttribute();
这样一来数据库就连接上了，搞点小例子吧
随便搞一个表实现用户简单的增删改查
- config.php
//因为增删改查都需要调用数据库
//就姑且放到这里用的时候引用一下就好
$dsn = "mysql:host=localhost;dbname=www.hm.com";
$username = "hmcom";
$password = "123456";
$pdo = new PDO($dsn,$username,$password);
$pdo->exec('set names utf8');
- index.php 列表页面
/**
* Created by PhpStorm.
* User: lenovo
* Date: 2020/12/24
* Time: 9:51
*/
//用户模块开发
include 'config.php';
$pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE,PDO::FETCH_ASSOC);
//这里可加可不加，加了统一设置，不加就写的时候设置
//这个是异常的时候，可以展示异常的信息，如果不写的话getMessage()就显示不出来
$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
$sql = "select * from `user` ";
//返回预处理对象
$smt = $pdo->prepare($sql);
//执行预处理语句 bool值
$smt->execute();
//查询并得到数据集合
//其实也可以这样
//if($smt->execute()){
//$result = $smt -> fetchAll();
//}
//不过看手册好像也没这么弄
$result = $smt -> fetchAll();
?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css" integrity="sha384-9aIt2nRpC12Uk9gS9baDl411NQApFmC26EwAOH8WgZl5MYYxFfc+NcPb1dKGj7Sk" crossorigin="anonymous">
<!-- JS, Popper.js, and jQuery -->
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/jquery.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/umd/popper.min.js" integrity="sha384-Q6E9RHvbIyZFJoft+2mJbHaEWldlvI9IOYy5n3zV9zzTtmI3UksdQRVvoxMfooAo" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.min.js" integrity="sha384-OgVRvuATP1z7JjHLkuOU7Xw704+h835Lr+6QL9UvYjZE3Ipu6Tp75j7Bh/kR0JKI" crossorigin="anonymous"></script>
<style>
td.th{
vertical-align: middle !important;
}
</style>
</head>
<body>
<div class="container">
<h2 class="page-header">
用户管理
</h2>
<table class="table table-striped table-bordered">
<tr>
<th>编号</th>
<th>用户名</th>
<th>密码</th>
<th>修改</th>
<th>删除</th>
</tr>
foreach ($result as $row){
echo "";
echo "{
$row['id']} ";
echo "{
$row['name']} ";
echo "{
$row['money']} ";
echo "]}'>修改 ";
echo "]}'>删除 ";
echo " ";
}
?>
</table>
<p >
<a class="btn btn-success btn-primary btn-large" href="add.php">添加用户</a>
</p>
</div>
</body>
</html>
//这个是异常的时候，可以展示异常的信息，如果不写的话getMessage()就显示不出来
$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
- del.php 删除页面
/**
* Created by PhpStorm.
* User: lenovo
* Date: 2020/12/24
* Time: 14:23
*/
include "config.php";
$id = $_GET['id'];
//用了下事务机制 想想打钱就知道了
//事务是多个sql执行的时候， 如果都成功则执行成功，事件结束，如果其中有一个失败，则回滚，事件最终也会结束
//开启事务
$pdo->beginTransaction();
//事务一般跟异常处理放在一起哟
try{
$sql = "delete from `user` where id = ?";
//返回一个预处理对象
$smt = $pdo->prepare($sql);
//把一个值绑定到一个参数
$smt->bindValue(1,$id,PDO::PARAM_INT);
// $smt->execute();这里返回的是bool值 执行预处理语句
if($smt->execute()){
echo '';
}
//成功提交并结束事务
$pdo->commit();
}catch (PDOException $pdoex){
$pdoex->getMessage();//得到异常位置的信息
$pdoex->getCode();//得到异常位置的code值
$pdoex->getLine();//得到异常位置的行数
//失败回滚并结束事务
$pdo->rollback();
}
- 修改页面
/**
* Created by PhpStorm.
* User: lenovo
* Date: 2020/12/24
* Time: 14:38
*/
include "config.php";
if(empty($_POST)){
$id = $_GET['id'];
echo $id;
$sql = "select * from `user` where id = ? ";
$smt = $pdo->prepare($sql);
$smt->bindValue(1,$id,PDO::PARAM_INT);
//执行预处理语句
$smt->execute();
//成功了的话，开始操作后面的
$result = $smt -> fetchAll();
foreach ($result as $row){
$name = $row['name'];
$money = $row['money'];
}
}else{
$id = $_POST['id'];
$name = $_POST['name'];
$money = $_POST['money'];
$sql = "update `user` set name='$name',money='$money' where id = $id ";
$smt = $pdo->prepare($sql);
if($smt->execute()){
echo '';
echo "";
}else{
echo '修改失败';
}
}
?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<h2 class="page-header">
用户管理
</h2>
<form action="" method="post" enctype="multipart/form-data">
<input type="text" name="name" value="$name?>">
<input type="text" name="money" value="$money?>">
<input type="hidden" name="id" value="$id?>">
<input type="submit" value="提交">
</form>
</body>
</html>
忘记写样式了
- 增加页面
/**
* Created by PhpStorm.
* User: lenovo
* Date: 2020/12/24
* Time: 14:38
*/
include "config.php";
if(empty($_POST)){
// echo '请重新提交';
}else{
$name = $_POST['name'];
$money = $_POST['money'];
$sql = "insert into `user`(name,money) value('{
$name}',$money)";
$smt = $pdo->prepare($sql);
if($smt->execute()){
//这里得到影响的行数
$num = $smt->rowCount();
echo "";
}
}
?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css" integrity="sha384-9aIt2nRpC12Uk9gS9baDl411NQApFmC26EwAOH8WgZl5MYYxFfc+NcPb1dKGj7Sk" crossorigin="anonymous">
<!-- JS, Popper.js, and jQuery -->
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/jquery.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/umd/popper.min.js" integrity="sha384-Q6E9RHvbIyZFJoft+2mJbHaEWldlvI9IOYy5n3zV9zzTtmI3UksdQRVvoxMfooAo" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.min.js" integrity="sha384-OgVRvuATP1z7JjHLkuOU7Xw704+h835Lr+6QL9UvYjZE3Ipu6Tp75j7Bh/kR0JKI" crossorigin="anonymous"></script>
</head>
<body>
<div class="container">
<h2 class="page-header">
用户管理
</h2>
<form action="add.php" method="post" enctype="multipart/form-data">
<div class="form-group">
<label for="">用户名：</label>
<input type="text" class="form-control" name="name" value="" placeholder="请输入用户名">
</div>
<div class="form-group">
<label for="">密码：</label>
<input type="text" class="form-control" name="money" value="" placeholder="请输入密码">
</div>
<input class="btn btn-primary btn-success" type="submit" value="提交">
</form>
</div>
</body>
</html>
如果有不足或者写错的地方欢迎大佬们指点指点谢谢。