跟我一起学写php单文件留言本

//实例化基础类

$base = new base($db_host,$db_user,$db_pass,$db_name,$db_char);

//定义基础类

class base{

private static $conn ;

var $err ;

//php5 构造函数 初始化连接

function __construct($db_host,$db_user,$db_pass,$db_name,$db_char=&＃39;GBK&＃39;){

/*连接数据库& 设置数据库字符集*/

@ $dbo = mysql_connect($db_host,$db_user,$db_pass) or die(&＃39;请检查是否数据库密码是否正确。&＃39;);

mysql_select_db($db_name,$dbo) or die (&＃39;数据库不存在，请确认是否正确安装&＃39;);

mysql_query("set names &＃39;$db_char&＃39;",$dbo);

$this->cOnn= $dbo;

}

//php4 构造函数

function base($db_host,$db_user,$db_pass,$db_name,$db_char=&＃39;GBK&＃39;){

$this->__construct($db_host,$db_user,$db_pass,$db_name,$db_char);

}

//增加留言

function add(&$data){

$username = $data[&＃39;username&＃39;]?$data[&＃39;username&＃39;]:&＃39;匿名&＃39;;

$title = $data[&＃39;title&＃39;];

$msg = $data[&＃39;msg&＃39;];

$sql = sprintf("insert into `liuyan` values(&＃39;&＃39;,&＃39;%s&＃39;,&＃39;%s&＃39;,&＃39;%s&＃39;,&＃39;%s&＃39;)",$username,$title,$msg,time());

mysql_query($sql,$this->conn);

return mysql_insert_id($this->conn);

}

//留言列表

function lists($p=0){

$c = 0;

if($p>0)$c=($p-1) * Per_page;

$limit = " limit ".$c.",".Per_page;

$where = &＃39;1&＃39;;

$r = &＃39;&＃39;;

$sql = sprintf("SELECT * from `liuyan` where &＃39;%s&＃39; $limit",$where.$limit);

$query = mysql_query($sql,$this->conn);

while($row = mysql_fetch_array($query)){

$r[] = $row;

}

return $r;

}

//统计分页

function page(){

$sql = "select count(id) from `liuyan`";

$query = mysql_query($sql,$this->conn);

$row = mysql_fetch_row($query);

$page[&＃39;totals&＃39;] = $row[0];

$page[&＃39;nums&＃39;] = ceil($row[0]/Per_page);

return $page;

}

//删除留言

function del($id){

$this->check();

if(is_array($id)){

$ids .= implode(&＃39;,&＃39;,$id);

}else{

$ids = $id;

}

$sql = "delete from `liuyan` where id in($ids)";

mysql_query($sql,$this->conn);

return mysql_affected_rows($this->conn);

}

//登录

function login($admin_name,$admin_pass){

$pass = md5($admin_name.$admin_pass.$admin_name);

$sql="select * from `admin` where `name`=&＃39;$admin_name&＃39; and `pass` = &＃39;$pass&＃39; ";

$query = mysql_query($sql,$this->conn);

$row = mysql_fetch_array($query);

if($row[&＃39;id&＃39;]>0){

$_SESSION=$row;

ShowMsg(&＃39;登录成功，欢迎管理员&＃39;.$_SESSION[&＃39;name&＃39;],3,&＃39;?do=manage&＃39;);

}else{

ShowMsg(&＃39;登录失败&＃39;.$_SESSION[&＃39;name&＃39;],3,&＃39;?do=login&＃39;);

}

}

//密码修改

function repass($admin_name,$admin_pass,$admin_id){

$this->check();

$pass = md5($admin_name.$admin_pass.$admin_name);

$sql = "UPDATE `admin` set name=&＃39;$admin_name&＃39; , pass=&＃39;$pass&＃39; where id=$admin_id";

mysql_query($sql,$this->conn);

return mysql_affected_rows($this->conn);

}

//退出

function logout(){

$this->check();

session_destroy();

}

//检查是否登录

function check(){

if($_SESSION[&＃39;name&＃39;] && $_SESSION[&＃39;pass&＃39;]){

//ShowMsg(&＃39;登录成功，欢迎管理员&＃39;.$_SESSION[&＃39;name&＃39;],3,&＃39;?do=manage&＃39;);

}else{

ShowMsg(&＃39;请先登录&＃39;.$_SESSION[&＃39;name&＃39;],3,&＃39;?do=login&＃39;);

}

}

function getErr(){

return $this->err;

}

function setErr(){

$this->err = mysql_error($this->conn);

}

}

//安全处理 递归函数

function Post_check($arr){

if(is_array($arr)){

foreach($arr as $n=>$k){

$data[$n] = Post_check($k);

}

}else{

return addslashes(trim($arr));

}

return $data;

}

//定时跳转

function ShowMsg($msg,$time=0,$url=&＃39;&＃39;){

echo "";

exit;

}

?>

//流程处理 不同操作显示不同界面

$do = $_REQUEST[&＃39;do&＃39;];

switch($do){

//添加留言

case &＃39;add&＃39;:

if($_POST[&＃39;do&＃39;] == &＃39;add&＃39;){

$data = Post_check($_POST);

if(@$base->add($data)>1){

echo &＃39;留言添加成功&＃39;;

}else{

echo $base->err;

}

}

break;

//删除留言

case &＃39;del&＃39;:

$data = Post_check($_POST);

$affected_rows=$base->del($data[&＃39;id&＃39;]);

if($affected_rows>0){

echo &＃39;成功删除&＃39;.$affected_rows.&＃39;行&＃39;.&＃39;返回&＃39;;

}else{

echo &＃39;删除失败&＃39;;

}

break;

//管理员修改密码

case &＃39;repass&＃39;:

$data = Post_check($_POST);

$r = $base->repass($data[&＃39;name&＃39;],$data[&＃39;admin_pass&＃39;],$data[&＃39;id&＃39;]);

if($r){

echo &＃39;密码修改成功&＃39;;

}else{

echo &＃39;密码修改失败&＃39;;

}

break;

//管理员退出登录

case &＃39;logout&＃39;:

$base->logout();

ShowMsg(&＃39;成功退出登录&＃39;.$_SESSION[&＃39;name&＃39;],3,&＃39;?do=&＃39;);

break;

//管理员登录

case &＃39;login&＃39;:

if($_POST[&＃39;admin_name&＃39;] && $_POST[&＃39;admin_pass&＃39;]){

$data = Post_check($_POST);

$base->login($data[&＃39;admin_name&＃39;],$data[&＃39;admin_pass&＃39;]);

}

?>

//管理留言

break;

case &＃39;manage&＃39;:

$base->check();

$p = intval($_GET[&＃39;p&＃39;]);

$lists = $base ->lists($p);

if(!$lists){

echo &＃39;留言为空&＃39;;

}else{

?>

break;

?>

//默认显示留言列表

default :

$p = intval($_GET[&＃39;p&＃39;]);

$lists = $base ->lists($p);

if(!$lists){

echo &＃39;留言为空&＃39;;

}else{

?>

break;

}?>