<?php $dsn = "mysql:dbname=phpblog;host=127.0.0.1"; # $PDO为 pdo基类的实例 $pdo = new PDO($dsn,'root','root');#1.如果不根据用户传过来的值进行操作,可以直接query sql $sql = "select * from stutable"; $stmt = $pdo->query($sql); #var_dump($stmt->fetchAll(2)); echo"<br>"; foreach ($stmt as $row) {print $row['id'] . "\t";print $row['name'] . "\t";print $row['date_'] . "\n"; }$id=1111; #2.sql中带变量进行查询 $stmt_=$pdo->query("select * from stutable where id ='{$id}' limit 1"); #var_dump($stmt_->fetch(2));#3.如果是根据用户传过来的值进行查询,为了防止sql注入,就需要预处理之后再进行查询$name = 'betty';//这里的$name是接收用户传过来的值,这里我们为了简洁,直接定位 $stmt->execute(array('name'=>$name)); var_dump($stmt->fetch(2)); ?>