email code

<?php
    //表单数据
    $to = $_POST['to'];
    $from = $_POST['from'];
    $cc =  $_POST['cc'];
    $title = $_POST['title'];
    $message = $_POST['message'];
    $submit = $_POST['submit'];
    
    //$submit为HMTL主页面中的提交按钮
    if($submit)
    {
        //$to为由HMTL页面传入的收信人地址
        if(!$to)
        {
            echo "<p align = center><font color = red size = 4>
                    <b>收件人地址不能为空！<br></b>请点击此处
                    <a href = javascript:history.go(-1);>返回</a></font></p>";
            exit();
        }
        
        //$title为由HTML页面传入的信件标题
        if(!$title) $title = "";
        
        //$message为由HTML页面传入的正文内容
        if(!$message) $message = "";
        
        //$from为由HMTL页面传入的发信人地址
        if($from)
        {
            $from = "From:$from \n";
            $reply = "Reply-To:$from \n";
        }
        else
        {
            $from = "";
        }
        
        //$cc为由HTML页面传入的抄送信息
        if($cc)
        {
            $cc = "CC:$cc";
        }
        else
        {
            $cc = "";
        }
        
        if(@mail($to,$title,$message,$from,$reply,$cc))
        {
            echo "<p align = center><font color = red size = 4><b>
                你的邮件发送成功！<br></b>请点击此处
                <a href = javascript:history.go(-1);>返回</a></font></p>";
            exit();
        }
        else
        {
            echo "<p align = center><font color = red size = 4>
                <b>对不起！你的邮件发送不成功！<br></b>请点击此处
                <a href = javascript:history.go(-1);>返回</a></font></p>";
            exit();
        }
    }
?>