php 写个上传下载类，保留备用

<?php
/*
require_once("ftp.php")
//参数为本地文件名，远程文件名,远程服务器，登录名，密码,后可加登录端口及超时时长
$myftp = new ftp("C://a.txt","mail/uaad.txt","192.168.0.17","ftp","ftp");
$myftp->upload();
$myftp = new ftp("xxyy.txt","mail/uaad.txt","192.168.0.17","ftp","ftp");
$myftp->download();

*/
class ftp
{
    //tangwf 2008-02-01 add
    //ftp类
    var $filename;  //本地要传入的文件
    var $remote_file;//远程的文件路径及命名
    var $ftp_server ;//远程登录主机
    var $ftpport; //ftp端口
    var $ftptime; //超时时长
    var $MyConnect = false; //本次ftp连接
    var $username = false;    //传入的用户名
    var $password = false;    //ftp连接密码

    //构造函数
    function ftp($filename,$remote_file,$ftp_server,$username,$password,$ftpport=21,$ftptime=90)
    {
        $this->filename=$filename;
        $this->remote_file=$remote_file;
        $this->ftp_server=$ftp_server;
        $this->username=$username;
        $this->password=$password;
        $this->ftpport=$ftpport;
        $this->ftptime=$ftptime;
    }

    //上传方法
    function upload()
    {
        $this->ftplogin();

        if (ftp_alloc($this->MyConnect, filesize($this->filename), $result))
            {
              if (!@ftp_put($this->MyConnect, $this->remote_file, $this->filename, FTP_BINARY))
                {
                  LogTxt("上传文件".$this->filename."到".$this->ftp_server.$this->remote_file."失败");
                }
              ftp_close($this->MyConnect);
            }
        else
            {
                LogTxt("上传失败".$result);
                ftp_close($this->MyConnect);
            }
    }
    //下载方法
    function download()
    {
        $this->ftplogin();
        if(!@ftp_get($this->MyConnect, $this->filename, $this->remote_file, FTP_BINARY))
        {
            LogTxt("下载文件".$this->remote_file."到".$this->filename."失败");
        }
        ftp_quit($this->MyConnect);
    }
    //登录方法
    function ftplogin()
    {
        $this->ftpconnect();
        if(! @ftp_login($this->MyConnect , $this->username, $this->password))
        {
            LogTxt("无法登录服务器:".$this->ftp_server."端口:".$this->ftpport."请检查用户名密码");
            ftp_close($this->MyConnect);
        }
    }
    //连接方法
    function ftpconnect()
    {
        $this->MyConnect = ftp_connect($this->ftp_server,$this->ftpport,$this->ftptime);
        if(!$this->MyConnect)
        {
            LogTxt("无法连接服务器:".$this->ftp_server."端口:".$this->ftpport);
        }
    }
    //写入日志
    function LogTxt($str)
    {
       $filename="log".date("Ymd").".txt";
       if (file_exists($filename)) 
        {
            if (!$handle =fopen($filename, 'a'))
            {
                echo "不能打开文件 $filename";
            }
        } 
        else 
        {
            if (!$handle =fopen($filename, 'w+'))
            {
                echo "不能创建文件 $filename";
            }
        }
       if (fwrite($handle,$str." ") === FALSE)
        {
            echo "不能写入到log文件 ".$filename;
        }
        fclose($handle);
    }
}
?>