powershell---高级函数的介绍

https://guhuajun.wordpress.com/2009/05/11/windows-powershell-v2-介绍（5）-高级函数（上）/

https://guhuajun.wordpress.com/2009/05/18/powershell-v2-介绍（6）-高级函数（中）/

https://guhuajun.wordpress.com/2009/05/25/powershell-v2-介绍（7）-高级函数（下）/