PHP 初学之登录查询小case

说明：如误入本文，请忽略即可，内容仅为记录。

功能：登录（不验证），查询所有列表，删除记录。--很简单，仅为熟悉代码。

// MySQL，新建数据库data，导入如下sql

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for stu
-- ----------------------------
DROP TABLE IF EXISTS `stu`;
CREATE TABLE `stu` (
  `stuid` int(11) NOT NULL AUTO_INCREMENT,
  `stuname` varchar(20) NOT NULL,
  `stusex` char(1) NOT NULL,
  `stuage` tinyint(4) NOT NULL,
  `stuadd` varchar(100) NOT NULL,
  PRIMARY KEY (`stuid`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8 COMMENT='学生表';

-- ----------------------------
-- Records of stu
-- ----------------------------
INSERT INTO `stu` VALUES ('', '篱笆', '男', '', '北京');
INSERT INTO `stu` VALUES ('', '绾绾', '女', '', '上海');

//新建login页面

 <?php
     if (isset($_POST['username']) && isset($_POST['pwd'])) {
         header("location:welcome.php?username={$_POST['username']}");
     }else{
         echo '用户名或密码不能为空！<br/>';
     }
 ?>

 <form action="" method="post">
     <table>
         <tr>
             <td>用户名：</td>
             <td>密码</td>
         </tr>
         <tr>
             <td><input type="text" name="username"></td>
             <td><input type="password" name="pwd"></td>
         </tr>
         <tr>
             <td><input type="submit" name="submit"></td>
         </tr>
     </table>

 </form>

//新建welcome页面

 welcome! user:
 <b>
     <?php
         if (isset($_GET['username'])) {
             echo $_GET['username'];
         }
     ?>
 </b>

 <br/>

 <script type="text/javascript">
 function go(){
     location.href='list.php';
 }
 </script>
 <input type="button" value="query list" onclick="go()"/>

//新建list页面

 <script type="text/javascript">
 function del(id){
     location.href='del.php?id='+id;
 }
 </script>

 <table>
     <tr>
         <th>stuid</th>
         <th>stuname</th>
         <th>stusex</th>
         <th>stuage</th>
         <th>stuadd</th>
     </tr>

 <?php

     $link = mysqli_connect('localhost','yourusername','yourpwd') or die(mysql_error());
     mysqli_select_db($link, 'data') or die(mysql_error);
     mysqli_query($link, 'set names utf8');

     $rs = mysqli_query($link, 'select * from stu');

     while ($row = mysqli_fetch_array($rs)) {
         $id = $row['stuid'];
         echo "<tr>";
         echo "<td>".$row['stuid']."</td>";
         echo "<td>".$row['stuname']."</td>";
         echo "<td>".$row['stusex']."</td>";
         echo "<td>".$row['stuage']."</td>";
         echo "<td>".$row['stuadd']."</td>";
         echo "<td>"."<a href='javascript:void()' onclick='del({$id})'>删除（不要点啊）</a>"."</td>";

         echo "</tr>";
     }

 ?>
 </table>

//新建del页面

 <?php
     if(isset($_GET['id'])){
         $link = mysqli_connect('localhost','yourusername','yourpwd') or die(mysql_error);
         mysqli_select_db($link, 'data') or die(mysql_error);
         $rs = mysqli_query($link, "delete from stu where stuid = {$_GET['id']}");
         var_dump($rs);

         echo "已经成功删除了id为{$_GET['id']}的记录<br/>";
     }
 ?>