Why does reflection not work well in .NET?

Question

I am interested to know the technical reasons: why does reflection not work very well in .NET?

Answer 1

Reflection works well, it's just a lot more than static code.

Say you have this piece of code:

typeof(SomeClass).GetMethod("SomeStaticMethod").
Invoke(null, new object[] { 1, 2, 3 });

This is the same as:

SomeClass.SomeStaticMethod(1, 2, 3);

But it should be obvious that the former has a lot more work. He should get information about the type, cross it to see if there is a SomeStaticMethod method, check which method it is, call the method on the instance or not, if it is static and pass an array of objects - these are the parameters, boxing / unpacking of integers and this case.

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This does not mean that it is really slow - it is just LOT slower than fully compiled scroll method calls and search queries. It should be - but I really think more about it, since compiled code is faster than dynamically searching for information on any system.