A php file upload class

<?php  
    /** 
     * 文件上传类 
     * bbs.it-home.org
     * */  
    class UpFile{  
        private  $filePath;                             //文件目的路径  
        private  $fileField;                            //默认$_FILES[$fileField],通过$_FILES环境变量获取上传文件信息  
        private  $originName;                           //源文件名  
        private  $tmpFileName;                          //临时文件名  
        private  $fileType;                             //文件类型  
        private  $fileSize;                             //文件大小  
        private  $newFileName;                          //新文件名  
        private  $allowType=array('jpg','gif','png');   //  
        private  $maxSize=2000000;                      //允许文件上传的最大度是2M  
        private  $isUserDefName=false;                  //是否采用用户自定义名  
        private  $userDefName;                          //用户定义名称  
        private  $isRandName=true;                      //是否随机命名  
        private  $randName;                             //系统随机名称  
        private  $errorNum=0;                           //错误号  
        private  $isCoverModer=true;                    //是否覆盖模式  
          
        function  __construct($options=array()){  
            $this->setOptions($options);        //设置上传时属性列表  
        }  
          
        function uploadFile($filefield){  
            $this->setOption('errorNum',0);                //设置错误位  
            $this->setOption('fileField',$filefield);      //设置fileField  
            $this->setFiles();                             //设置文件信息  
            $this->checkValid();                           //判断合法性  
            $this->checkFilePath();                        //检查文件路径  
            $this->setNewFileName();                       //设置新的文件名  
            if($this->errorNum<0)  
            return $this->errorNum;  
         return  $this->copyFile();  //上传文件  
        }  
        private  function setOptions($options=array()){  
            foreach ($options as $key=>$val){  
                if(!in_array($key,array('filePath','fileField','originName','allowType','maxSize','isUserDefName','userDefName','isRandName','randName')))   
                continue;  
                $this->setOption($key,$val);  
            }  
        }  
        private function setFiles(){  
            if($this->getFileErrorFromFILES!=0){  
                $this->setOptions('errorNum',-1);  
                return $this->errorNum;  
            }  
            $this->setOption('originName',$this->getFileNameFromFILES());  
            $this->setOption('tmpFileName',$this->getTmpFileNameFromFILES());  
            $this->setOption('fileType',$this->getFileTypeFromFILES());  
            $this->setOption('fileSize',$this->getFileSizeFromFILES());  
          
        }  
        private function setOption($key,$val){  
            $this->$key=$val;  
        }  
        private  function setNewFileName(){  
            if($this->isRandName==false&&$this->isUserDefName==false){  
                $this->setOption('newFileName',$this->originName);  
            }elseif ($this->isRandName==true&&$this->isUserDefName=false){  
                $this->setOption('newFileName',$this->proRandName().'.'.$this->fileType);  
            }elseif ($this->isRandName==false&&$this->isUserDefName=true){  
                $this->setOption('newFileName',$this->userDefName);  
            }else {  
                $this->setOption('errorNum',-4);  
            }  
        }  
        private function checkValid(){  
            $this->checkFileSize();  
            $this->checkFileType();  
        }  
        private function checkFileType(){  
            if(!in_array($this->fileType,$this->allowType)){  
                $this->setOption('errorNum',-2);  
            }else {  
                return $this->errorNum;  
            }  
        }  
        private  function checkFileSize(){  
            if($this->fileSize>$this->maxSize){  
                $this->setOption('errorNum',-3);  
            }else {  
                return $this->errorNum;  
            }  
        }  
        private  function checkFilePath(){  
            if(!file_exists($this->filePath)){  
                if($this->isCoverModer){  
                    $this->makePath();  
                }else {  
                    $this->setOption('errorNum',-6);  
                }  
            }  
        }  
        private function proRandName(){  
            $tmpStr= "abcdefghijklmnopqrstuvwxyz0123456789";  
            $str="";  
            for ($i=0;$i<8;$i++){  
                $num=rand(0,strlen($tmpStr));  
                $str.=$tmpStr[$num];  
            }  
            return $str;  
        }  
        private function makePath(){  
            if(!@mkdir($this->filePath,0755)){  
                $this->setOption('errorNum',-7);  
            }  
        }  
        private function copyFile(){  
            $filePath=$this->filePath;  
            if($filePath[strlen($filePath)-1]!='/'){  
                $filePath.='/';  
            }  
            $filePath.=$this->newFileName;  
            if(!@move_uploaded_file($this->tmpFileName,$filePath)){  
                $this->setOption('errorNum',-5);  
            }  
            return  $this->errorNum;  
        }  
        function getNewFileName(){  
           return   $this->newFileName;  
        }  
        private function getFileErrorFromFILES(){  
            return  $this->fileField['error'];  
        }  
        private function getFileTypeFromFILES(){  
            $str=$this->fileField['name'];  
            $aryStr=split("\.",$str);                //将字符串分割到数组中  
            $ret=strtolower($aryStr[count($aryStr)-1]);  
            return  $ret;  
        }  
        private function getFileNameFromFILES(){  
            return $this->fileField['name'];  
        }  
        private function getTmpFileNameFromFILES(){  
            return $this->fileField['tmp_name'];  
        }  
        private function getFileSizeFromFILES(){  
            return $this->fileField['size'];  
        }  
        public function getErrorMsg(){  
            $str="上传文件出错：";  
            switch ($this->errorNum){  
                case -1:  
                    $str.="未知错误！";  
                    break;  
                case -2:  
                    $str.="未允许类型！";  
                    break;  
                case -3:  
                    $str.="文件过大！";  
                    break;  
                case -4:  
                    $str.="产生文件名出错！";  
                    break;  
                case -5:  
                    $str.="上传失败！";  
                    break;  
                case -6:  
                    $str.="目录不存在！";  
                    break;  
                case -7:  
                    $str.="建立目录失败！";  
                    break;  
            }  
            return $str;  
        }  
    }      
?>