$_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

    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;   
}