.Net Framework Essentials

COM+ Services in .NET

COM programming requires lots of housekeeping and infrastructure-level code to build large-scale, enterprise applications. Making it easier to develop and deploy transactional and scalable COM applications, Microsoft released Microsoft Transaction Server (MTS). MTS allows you to share resources, thereby increasing the scalability of an application. COM+ Services were the natural evolution of MTS. While MTS was just another library on top of COM, COM+ Services were subsumed into the COM library, thus combining both COM and MTS into a single runtime.

COM+ Services have been very valuable to the development shops using the COM model to build applications that take advantage of transactions, object pooling, role-based security, and so forth. If you develop enterprise .NET applications, the COM+ Services in .NET are a must.

In the following examples, rather than feeding you more principles, we’ll show you examples for using major COM+ Services in .NET, including examples on transactional programming, object pooling, and role-based security. But before you see these examples, let’s talk about the key element—attributes—that enable the use of these services in .NET.

Attribute-Based Programming

Attributes are the key elements that help you write less code and allow an infrastructure to automatically inject the necessary code for you at runtime. If you’ve used IDL (Interface Definition Language) before, you have seen the in or out attributes, as in the following ...