第二个参数就是设置的属性 可为以下几个值：FILE_ATTRIBUTE_ARCHIVE The file is an archive file. Applications use this attribute to files for backup or removal. FILE_ATTRIBUTE_HIDDEN The file is hidden. It is not included in an ordinary directory listing. FILE_ATTRIBUTE_NORMAL The file has no other attributes set. This attribute is valid only if used alone. FILE_ATTRIBUTE_READONLY The file is read-only. Applications can read the file but cannot write to it or delete it. FILE_ATTRIBUTE_SYSTEM The file is part of the operating system or is used exclusively by it. FILE_ATTRIBUTE_TEMPORARY The file is being used for temporary storage. File systems attempt to keep all of the data in memory for quicker access rather than flushing the data back to mass storage. A temporary file should be deleted by the application as soon as it is no longer needed. 此处用FILE_ATTRIBUTE_NORMAL清除任何文件属性
可为以下几个值：FILE_ATTRIBUTE_ARCHIVE
The file is an archive file. Applications use this attribute to files for backup or removal. FILE_ATTRIBUTE_HIDDEN
The file is hidden. It is not included in an ordinary directory listing. FILE_ATTRIBUTE_NORMAL
The file has no other attributes set. This attribute is valid only if used alone. FILE_ATTRIBUTE_READONLY
The file is read-only. Applications can read the file but cannot write to it or delete it. FILE_ATTRIBUTE_SYSTEM
The file is part of the operating system or is used exclusively by it. FILE_ATTRIBUTE_TEMPORARY
The file is being used for temporary storage. File systems attempt to keep all of the data in memory for quicker access rather than flushing the data back to mass storage. A temporary file should be deleted by the application as soon as it is no longer needed. 此处用FILE_ATTRIBUTE_NORMAL清除任何文件属性