Question

Is there a way to have named arguments like in perl/python

for example

object.method(arg1 => value1, arg2 => value2, arg3 => 0);

in C# prior to C# 4.0?

Answer 1

method named arguments are C# 4.0 feature. (You can t have method optional parameters in C# < 4.0)

Answer 2

It is not possible before C# 4.0.

BTW, there is no such thing as C# 2.5.

Answer 3

While not an exact match for named arguments, there is something in C# 3.0 for constructors that is similar called "object initializers" that let you define values for public properties when you use the new operator. This lets you do stuff like this:

Person p = new Person()
{
    FirstName = "John",
    LastName = "Doe",
    Address = new Address()
    {
        Street = "1234 St.",
        City = "Phoenix"
    }
};

Now in order to utilize this you have invoke the new operator (so it won t work for methods) and the properties that you are setting need to have the same access that they would have to allow you to do this:

Person p = new Person();

p.FirstName = "John";
p.LastName = "Doe";

Address a = new Address();
a.Street = "1234 St.";
a.City = "Phoenix";

p.Address = a;

So this won t let you circumvent public get but protected set properties (you can t make a property only initialized via this method). This can make your code more readable, though not to the degree that named arguments can.

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