PHP 留言板练习

login页面
<form action="loginchuli.php" method="post">
    <div>用户名：<input type="text" name="uid" /></div>
    <div>密码：<input type="text" name="pwd" /></div>
    <input type="submit" value="登录" />
</form>
loginchuli页面
<?php
session_start();
$uid = $_POST["uid"];
$pwd = $_POST["pwd"];

include("../DBDA.php");
$db = new DBDA();

$sql = "select count(*) from yuangong where username=‘{$uid}‘ and password = ‘{$pwd}‘";

$z = $db->StrQuery($sql);

if($z == 1)
{
    $_SESSION["uid"] = $uid;
    header("location:main.php");
}
else
{
    header("location:login.php");
}

<?php
session_start();

if(empty($_SESSION["uid"]))
{
    header("location:login.php");
    exit;
}

$uid = $_SESSION["uid"];
include("../DBDA.php");
$db = new DBDA();

?>
<br /><br />
<a href="main.php">查看信息</a> <a href="tuichu.php">退出系统</a>

<br />
<h2>信息发送</h2>

<form action="fabuchuli.php" method="post">
<div>接收人：
    <select name="jieshou">
        <option value="suoyou">所有人</option>
        <?php
            $sql = "select firend from firend where me=‘{$uid}‘";
            $attr = $db->Query($sql);
            
            foreach($attr as $v)
            {
                $sqln = "select Name from yuangong where username=‘{$v[0]}‘";
                $name = $db->StrQuery($sqln);
                
                echo "<option value=‘{$v[0]}‘>{$name}</option>";
            }
            
        ?>
    </select>
</div>
<br />
<div>
    信息内容：
    <textarea name="neirong">
    </textarea>
</div>
<br />
<div>
    <input type="submit" value="发送" />
    <input type="reset" value="复位" />
</div>
</form>

<?php
session_start();

include("../DBDA.php");
$db = new DBDA();

$jieshou = $_POST["jieshou"];
$neirong = $_POST["neirong"];
$uid = $_SESSION["uid"];
$time = date("Y-m-d H:i:s");

$sql = "insert into liuyan values(‘‘,‘{$uid}‘,‘{$jieshou}‘,‘{$time}‘,‘{$neirong}‘,false)";

if($db->Query($sql,0))
{
    header("location:fabu.php");
}
else
{
    echo "发布失败！";
}

<a href="fabu.php">发布信息</a> <a href="tuichu.php">退出系统</a>
<br />
<br />
<table width="100%" border="1" cellpadding="0" cellspacing="0">
<tr>
    <td>发送人</td>
    <td>发送时间</td>
    <td>接收人</td>
    <td>信息内容</td>
</tr>
<?php
session_start();

if(empty($_SESSION["uid"]))
{
    header("location:login.php");
    exit;
}

$uid = $_SESSION["uid"];

include("../DBDA.php");
$db = new DBDA();


$sql = "select * from liuyan where recever=‘{$uid}‘ or recever=‘suoyou‘";

$attr = $db->Query($sql);

foreach($attr as $v)
{
    //处理发送者姓名
    $sqlname = "select Name from yuangong where username=‘{$v[1]}‘";
    $name = $db->StrQuery($sqlname);
    
    //处理接收者姓名
    $jieshou = "";
    if($v[2]=="suoyou")
    {
        $jieshou = "所有人";
    }
    else
    {
        $sqln = "select Name from yuangong where username=‘{$uid}‘";
        $jieshou = $db->StrQuery($sqln);
    }
    
    echo "<tr>
    <td>{$name}</td>
    <td>{$v[3]}</td>
    <td>{$jieshou}</td>
    <td>{$v[4]}</td>
    </tr>";
}


?>
</table>

<?php
session_start();

unset($_SESSION["uid"]);
header("location:login.php");