Static Vs Instance method performance differences
Posted March 27, 2005 
Comments(0) I think it is too late to post this info. Still I can see some question related to this topic in public newsgroups, hence this entry.
Here is my simple class.
public class MyClass
{
public static void StaticHello()
{
Console.WriteLine(”Hello”);
}
public void InstanceHello()
{
Console.WriteLine(”Hello”);
}
}
Here is a snippet from main method.
//Staic Method Invokation
MyClass.StaticHello();
//Instance method invokation
MyClass myClass = new MyClass();
myClass.InstanceHello();
Both methods will do the same. Now question. What about the performance? Which one should I use? Well, all depends on what you want J
If you look the IL code for this app,
.locals init ([0] class StaticMethodTest.MyClass myClass)
IL_0000: call void StaticMethodTest.MyClass::StaticHello()
IL_0005: newobj instance void StaticMethodTest.MyClass::.ctor()
IL_000a: stloc.0
IL_000b: ldloc.0
IL_000c: callvirt instance void StaticMethodTest.MyClass::InstanceHello()
IL_0011: ret
ie static method is using calll and instance method is using callvirt instruction. Even if you edit your IL and replace callvirt with call, application will work. But, callvirt will do null checking of the object, before it try to invoke methods. Obviously, static methods will be faster than instance method, since there is no null checking. Again, the difference is too small.
