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  • 5月13 PDO数据访问抽象层

    方法1:较简单的

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>PDO方法1整理</title>
    </head>
    
    <body>
    <?php
    //造DSN 格式为:驱动名:dbname=数据库名;host=服务器地址
    $dsn = "mysql:dbname=mydb;host=localhost";
    
    //造PDO对象
    $pdo = new PDO($dsn,"root","");
    
    //写SQL语句
    $sql = "select * from Info";
    
    /*//执行SQL语句   可以但是一般不用
    $v = $pdo->query($sql);
    //返回的对象比较特殊,可以直接用循环遍历
    foreach($v as $a)
    {
    	echo $a[0];
    }*/
    
    //预处理,先把SQL语句放到服务器上等待我们给他指令去执行
    //准备一条SQL语句,返回PDO对象
    $stm = $pdo->prepare($sql);
    
    //执行准备好的SQL语句,成功返回true,失败返回false
    if($stm->execute())
    {
    	//输出的方式
    	//1.逐行取数据
    	//var_dump($stm->fetch());//读取的数据有索引也有关联数组,
    	//里面可以写参数
    	//var_dump($stm->fetch(PDO::FETCH_ASSOC));//关联数组
    	//var_dump($stm->fetch(PDO::FETCH_BOTH));//都有
    	//var_dump($stm->fetch(PDO::FETCH_NUM));//索引数组
    	
    	//2.读取所有的数据
    	//var_dump($stm->fetchAll());//参数同上
    	
    	//3.读取某一列
    	//var_dump($stm->fetchColumn(1));//里面是索引
    	
    	//4.返回对象
    	//var_dump($stm->fetchObject());
    }
    else
    {
    	echo "执行失败";	
    }
    ?>
    
    </body>
    </html>
    

      注意pdo中的输出方式:

    逐行读取数据-----$stm->fetch();      #包含索引数组和关联数组

    读取全部数据-----$stm->fetchAll();   #包含索引数组和关联数组

    括号里面可以写参数的,两个的方法都是一样的,常见的有:

    $stm->fetch(PDO::FETCH_ASSOC);    #关联数组
    $stm->fetch(PDO::FETCH_BOTH);     #都有
    $stm->fetch(PDO::FETCH_NUM);     #索引数组

    返回某一列-----$stm->fetchColumn(1);        #里面是索引

    返回对象-------$stm->fetchObject();

    方法2:以添加数据举例,分为两种,索引数组和关联数组

    索引数组

    <title>PDO方法2整理</title>
    </head>
    
    <body>
    <?php
    //索引数组
    
    //造对象
    $dsn = "mysql:dbname=mydb;host=localhost";
    $pdo = new PDO($dsn,"root","");
    
    //写SQL语句
    //$sql = "insert into Nation values(?,?)";
    
    //预处理
    $stm = $pdo->prepare($sql);
    
    //给参数绑定值,较为麻烦不建议
    /*$stm->bindParam(1,$code);
    $stm->bindParam(2,$name);
    $code = "p002";
    $name = "回k";*/
    
    //造数组
    $attr = array("p111","张三");
    
    //执行
    if($stm->execute($attr))
    {
    	echo "添加成功";	
    }
    else
    {
    	echo "添加失败";	
    }
    ?>
    
    </body>
    </html>
    

      关联数组

    <title>PDO方法2整理</title>
    </head>
    
    <body>
    
    <?php
    //关联数组
    //造对象
    $dsn = "mysql:dbname=mydb;host=localhost";
    $pdo = new PDO($dsn,"root","");
    
    //写SQL语句
    $sql = "insert into Nation values(:code,:name)";
    
    //预处理
    $stm = $pdo->prepare($sql);
    
    //给参数绑定值,麻烦不建议
    /*$stm->bindParam("code",$code,PDO::PARAM_STR);
    $stm->bindParam("name",$name,PDO::PARAM_STR);
    $code = "p003";
    $name = "aaaa";
    */
    
    //造数组
    $attr = array("code"=>"p005","name"=>"bbbb");
    
    //执行
    if($stm->execute($attr))
    {
    	echo "添加成功";
    }
    else
    {
    	echo "添加失败";	
    }
    ?>
    
    </body>
    </html>
    

      另一种方法是利用表单的,更加方便,都可以使用

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>无标题文档</title>
    </head>
    
    <body>
    <form action="pdo2.php" method="post">
    <div>代号:<input type="text" name="code" /></div><br />
    
    <div>名称:<input type="text" name="name" /></div><br />
    
    <div><input type="submit" value="提交" /></div>
    </form>
    </body>
    </html>
    

      

    <title>PDO方法2整理</title>
    </head>
    
    <body>
    
    <?php
    //关联数组
    //造对象
    $dsn = "mysql:dbname=mydb;host=localhost";
    $pdo = new PDO($dsn,"root","");
    
    //写SQL语句
    $sql = "insert into Nation values(:code,:name)";
    
    //预处理
    $stm = $pdo->prepare($sql);
    
    //执行
    if($stm->execute($_POST))
    {
    	echo "添加成功";
    }
    else
    {
    	echo "添加失败";	
    }
    ?>
    </body>
    </html>
    

      

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  • 原文地址:https://www.cnblogs.com/Duriyya/p/5488843.html
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