$_FILES[

$_FILES['file']['error']值 

UPLOAD_ERR_OK: 0 //正常，上传成功 

UPLOAD_ERR_INI_SIZE: 1 //上传文件大小超过服务器允许上传的最大值，php.ini中设置upload_max_filesize选项限制的值 

UPLOAD_ERR_FORM_SIZE: 2 //上传文件大小超过HTML表单中隐藏域MAX_FILE_SIZE选项指定的值 

UPLOAD_ERR_NO_TMP_DIR: 6 //没有找不到临时文件夹 

UPLOAD_ERR_CANT_WRITE: 7 //文件写入失败 

UPLOAD_ERR_EXTENSION: 8 //php文件上传扩展没有打开 

UPLOAD_ERR_PARTIAL: 3 //文件只有部分被上传

switch($_FILES[$field]['error']) {  

    case 1:    

        // 文件大小超出了服务器的空间大小    
        $this->setError("The file is too large (server).");    
break;   

case 2:    
        // 要上传的文件大小超出浏览器限制    
        $this->setError("The file is too large (form).");    
        break;    

    case 3:    
        // 文件仅部分被上传    
        $this->setError("The file was only partially uploaded.");    
        break;    

    case 4:    
        // 没有找到要上传的文件    
        $this->setError("No file was uploaded.");    
        break;    

    case 5:    
        // 服务器临时文件夹丢失    
        $this->setError("The servers temporary folder is missing.");    
        break;    

    case 6:    
        // 文件写入到临时文件夹出错    
        $this->setError("Failed to write to the temporary folder.");    
        break;    
}