php+xml留言板实例教程二

<script>ec(2);</script>

这是一个xml 解析类

class Message_XML extends DOMDocument
{
 const file_name = "e:/myphp/xmldom/xml/message.xml";
 private $root; //根节点
 private $PageNo; //当前页
 private $allNum; //记录总数
 private $PageSize; //页大小
 private $allPages; //总页数
 public function __construct()
 {
   parent::__construct();
   if(!file_exists(self::file_name))
   {
    $xmlStr = "";
    $this -> loadXML($xmlStr);
    $this -> save(self::file_name);
   }else{
    $this -> load(self::file_name);
   }
   $this -> root = $this -> documentElement;
   $this -> get_pagemsg();
 }
 //得到页信息
 private function get_pagemsg()
 {
   $this -> PageSize = 3; //页大小
   $allNode = $this -> getElementsByTagName("record");
   $this -> allNum = $allNode -> length; //记录总数
   $this -> allPages = ceil($this -> allNum / $this -> PageSize); //总页数
   $this -> PageNo = $_GET["PageNo"];
   if($this -> PageNo PageNo))
   {
    $this -> PageNo = 1;
   }else if($this -> PageNo > $this -> allPages){
    $this -> PageNo = $this -> allPages;
   }
   $this -> PageNo = (int)$this -> PageNo;
 }
 //显示留言
 public function show_message()
 {
   $start_num = ($this -> PageNo - 1) * $this -> PageSize; //记录开始数
   $end_num = $start_num + $this -> PageSize - 1; //记录结束数
   $allNode = $this -> getElementsByTagName("record");
   $i = 0;
   foreach($allNode as $v)
   {
    if($i >= $start_num && $i     {
     $autoid = $v -> getElementsByTagName("autoid") -> item(0) -> nodeValue;
     $subject = $v -> getElementsByTagName("subject") -> item(0) -> nodeValue;
     $content = $v -> getElementsByTagName("content") -> item(0) -> nodeValue;
     $str = "

留言标题：$subject

留言内容：

        $content

";
     $str .= "

编辑 删除

";
     print $str;
    }
    $i++;
   }
   $this -> get_pageCode();
 }
 //得到当前页码
 public function get_pageCode()
 {
  $str = "

当前页：".$this -> PageNo." / ".$this -> allPages."   首页 上一页 下一页 末页";
  $str .= "   ";
  print $str;
 }
 //添加留言页面
 public function post_message()
 {
   print "

";
   print "

标题：

";
   print "

内容：

";
   print "

";
 }
 //添加留言
 public function add_message($Subject,$Content)
 {
   $autoid = microtime();  //留言ID
   $autoid = substr(strrchr(str_replace(" ","",$autoid),"."),1);
   $node_top = $this -> root ->appendChild($this -> createElement("record"));
   $node_top -> appendChild($this -> createElement("autoid",$autoid));
   $node_top -> appendChild($this -> createElement("subject",$Subject));
   $node_top -> appendChild($this -> createElement("content",$Content));
   $this -> save(self::file_name);
   echo "<script>alert('添加留言成功！');window.location='".$_SERVER['PHP_SELF']."?PageNo=".$_GET['PageNo']."'</script>";
 }
 //清空留言
 public function clear_message()
 {
   $fp = @ fopen(self::file_name,"w+");
   if($fp)
   {
    $str = "";
    fwrite($fp,$str);
    fclose($fp);
    echo "<script>alert('清空成功！');window.location='".$_SERVER['PHP_SELF']."'</script>";
   }else{
    echo "<script>alert('清空失败！');history.back();</script>";
   }
 }
 //设置节点路径和操作对象ID
 private function set_nodePath($AutoID)
 {
   $xpath = new DOMXPath($this);
   $node_top = $xpath -> query("//record[autoid=$AutoID]");
   return $node_top;
 }
 //删除留言
 public function delete_message($AutoID)
 {
   $node_top = $this -> set_nodePath($AutoID);
   $this -> root -> removeChild($node_top -> item(0));
   $this -> save(self::file_name);
   echo "<script>alert('删除成功！');location='".$_SERVER['PHP_SELF']."?PageNo=".$_GET['PageNo']."'</script>";
 }
 //编辑留言页面
 public function edit_message($AutoID)
 {
   $node_top = $this -> set_nodePath($AutoID);
   //取值方法1
   //$subject = $node_top -> item(0) -> getElementsByTagName("subject") -> item(0) -> nodeValue;
   //$content = $node_top -> item(0) -> getElementsByTagName('content') -> item(0) ->nodeValue;
   //取值方法2
   foreach($node_top -> item(0) -> childNodes as $v)
   {
    $value[] = $v -> textContent; //注意：这里的$value必须这样写成一个数组，否则要出错
   }
   print "

";
   print "

标题：

";
   print "

内容：$value[2]

";
   print "

"; 
 }
 //编辑留言
 public function save_message($AutoID,$Subject,$Content)
 {
   $node_top = $this -> set_nodePath($AutoID);
   $replace_info[0] = $AutoID;
   $replace_info[1] = $Subject;
   $replace_info[2] = $Content;
   $i = 0;
   foreach($node_top -> item(0) -> childNodes as $v)
   {
    $new_content = $this -> createTextNode($replace_info[$i]);
    $v -> replaceChild($new_content,$v -> lastChild);
    $i++;
   }
   $this -> save(self::file_name);
   echo "<script>alert('编辑成功！');location='".$_SERVER['PHP_SELF']."?PageNo=".$_GET['PageNo']."'</script>";
 }
}
?>