Question

I’ve noticed that there are many static methods in FCL that affect only single object, for example Array.Resize. What’s the point making them static?

Answer 1

Instance methods can only modify the member properties of an object. In your example of Array.Resize, the method modifies the array reference itself, which is why it is static and takes the parameter by reference.

When you do this:

int[] arr = ...;
Array.Resize(ref arr, 10);

the arr reference itself is modified, which would not be possible by calling a method on arr.

Alternatively, in a language such as Java which does not support passing by reference, it would be declared to return the new array.