练习：投票

主页面

<?php
include("./dbda.class.php");
$db = new dbda();
$sql = "select * from diaoyantimu limit 0,1";
$attr = $db->Query($sql);
echo "<div>{$attr[0][1]}</div>";

?>
    <div id="tp">
    <form action="TiJiao.php" method="post">
    <div>
    <?php
    $sql1 = "select * from diaoyanxuanxiang";     
    $att = $db->Query($sql1);
    foreach($att as $v)
    {
        echo"<input type='checkbox' value='{$v[0]}' name='xx[]'/>{$v[1]}<br />";
    }
    
    ?>
    </div>
    <div><input type="submit" value="提交" />&nbsp;&nbsp;<input type="button" value="查看结果" onclick="show()" /></div>
    </form>
    </div>
    
    <div style="display:none;" id="jieguo">  
    <?php
    $sql2 = "select sum(Numbers) from diaoyanxuanxiang where TiMuDaiHao='{$attr[0][0]}'";     
    $sumnumbers = $db->Query($sql2);
    foreach($att as $v1)
    {
        $bfb = ($v1[2]/$sumnumbers[0][0])*100;
        $bfb = round($bfb,2);
        echo "<div class='ff'>$v1[1]&nbsp;&nbsp;</div>
              <div class='ff'>{$v1[2]}&nbsp;({$bfb}%)</div>
              <div class='ff' style=' 100px; height:10px; border:1px solid red'><div style='height:10px; {$bfb}%; background-color:red'></div></div> <br />";
    }
    ?>
    <input type="button" value="返回"  onclick="showfh()" />
    </div>
    

JS页面：控制页面隐藏与显示

<script type="text/javascript">
function show()
{
    document.getElementById("tp").style.display="none";
    document.getElementById("jieguo").style.display="block";
}
function showfh()
{
    document.getElementById("tp").style.display="block";
    document.getElementById("jieguo").style.display="none";
}

</script>

封装数据库类

<?php
class dbda
{
    public $host = "localhost";  //数据库地址
    public $uid = "root";  //数据库用户名
    public $pwd = "";  //数据库密码
    //执行sql语句
    //参数：sql代表要执行的sql语句  type是sql语句的类型0代表查询1代表其他   db代表要操作的数据库
    public function Query($sql,$type=0,$db="mydb") 
    {
        //1.造连接对象
        $dbconnect = new MySQLi($this->host,$this->uid,$this->pwd,$db);
        !mysqli_connect_error() or die("连接失败！");
        $result = $dbconnect->query($sql);
        if($type ==0)
        {
            return $result->fetch_all();
        }
        else
        {
            return $result;
        }
    }
}