Can parameters be constant?

Question

I\'m looking for the C# equivalent of Java\'s final. Does it exist?

Does C# have anything like the following:

public Fo         


        

Answer 1

This is now possible in C# version 7.2:

You can use the in keyword in the method signature. MSDN documentation.

The in keyword should be added before specifying a method's argument.

Example, a valid method in C# 7.2:

public long Add(in long x, in long y)
{
    return x + y;
}

While the following is not allowed:

public long Add(in long x, in long y)
{
    x = 10; // It is not allowed to modify an in-argument.
    return x + y;
}

Following error will be shown when trying to modify either x or y since they are marked with in:

Cannot assign to variable 'in long' because it is a readonly variable

Marking an argument with in means:

This method does not modify the value of the argument used as this parameter.