using static

[pgraeve]

I find it much easier if a class is going to have an empty constructor to make the class's properties and methods static. But I haven't read or seen anything on the "ramifications" of using static a bunch. One one hand it seems as though it would help the system's performance since static methods and properties are loaded on system startup - but does this dramatically affect the system's "startup" time; and memory usage - or enough to worry about it anyway? And is calling static methods etc. offer any significant performance increase over intializing a class with an empty constructor and then utilizing its methods etc.? Has anyone discovered some good "rules of thumb" for determining when to make a method or property static? I typically create static sql connection strings, color properties, etc... based on the above questions, is this a good idea or not?

[Christian Graus]

If a method does not rely on state within the class ( i.e. member variables of a specific instance of a class ), then it should be static, or possibly part of a fascade class. Christian I have drunk the cool-aid and found it wan and bitter. - Chris Maunder

[Heath Stewart]

As Christian implied, you should use instance members when the class requires state for each instantiation. Statics are also executed synchronously within a single AppDomain so forget multi-threaded applications. Finally, this makes for a terrible object-oriented design and throws polymorphism out the window since you can neither mark a static member as abstract nor override an inheritted static member. You're basically turning the .NET Framework into a procedural construct. If that's what you're after, you don't want object-oriented runtimes like the .NET CLR or Java Runtime Environment. Static members are best reserved for class factories, non-instance operations (like binary operators, non-class specific methods like Control.MousePosition, and the like). Everything else should be an instance member. In a good OO design, you'll end up using mostly instance members.

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