<?php $dbhost='localhost'; $dbuser='root'; $dbpass='123456'; $dbname='products'; $connect=mysql_connect($dbhost,$dbuser,$dbpass); if(!$connect) exit('数据库连接失败！'); mysql_select_db($dbname,$connect); mysql_query('set names utf8'); //查询 $sql="SELECT * FROM `category`"; $result=mysql_query($sql); while($row=mysql_fetch_array($result)){  echo $row['id']; } //插入 $sql="INSERT INTO `category` (`id`,`name`) VALUES (NULL,'".$name."')"; $result=mysql_query($sql); if(mysql_affected_rows()){  echo '插入成功，插入ID为：',mysql_insert_id(); }else{  echo '插入失败：',mysql_error(); } //修改 $sql="UPDATE `category` SET `name`='".$name."' WHERE `id`='".$id."'"; $result=mysql_query($sql); if(mysql_affected_rows()){  echo '修改成功！'; } //删除 $sql="DELETE FROM `category` WHERE `id`='".$id."'"; $result=mysql_query($sql); if(mysql_affected_rows()){  echo '删除成功！'; } //关闭连接 mysql_close($connect); ?>