Appendix A. Introduction to WSH
Since the release of Windows 2000, each operating system Microsoft has produced comes with a technology called the Windows Script Host, more commonly known as WSH, which allows scripts to execute directly on the client computer. WSH-based scripts can open and read files, attach to network resources, automate Word and Excel to create reports and graphs, automate Outlook to manipulate email and news, change values in the registry, and so on. The reason these scripts can be so versatile is that WSH supports scripting access to all Component Object Model (COM) objects installed on the client computer.
COM is a Microsoft technology that defines each host component as a set of objects, thus allowing you to automate and manipulate virtually anything you require on a client computer. When someone needs to create or manage a new component on a Windows-based host, he creates a COM interface, which can be thought of as the definition of the object, and the entire set of operations that can be performed on that object. Interfaces normally are stored in Dynamic Link Library (DLL) files.
So, for example, if you want to manipulate a file, you actually need to manipulate a file COM object. The file COM object definition will be stored in an interface held in a DLL. The interface will define all of the operations, such as creating the file, deleting the file, writing to the file, and so on. The interface will also define a series of object properties, such as the ...