Sample: void Foo(int i1, int i2 = 0, DateTime dt = default(DateTime), string s = null) Which of the method Foo invocation is correct?

288.

Sample:

void Foo(int i1, int i2 = 0, DateTime dt = default(DateTime), string s = null)
Which of the method Foo invocation is correct?

Foo(10,,,"abc");

Foo(10, dt: DateTime.Now);

Foo(i2:10, dt:DateTime.Now);

Foo(i2:10, s:"abc", i1:5);

Answers 2 and 4

View Description

The value for i1 argument must be always passed and arguments list cannot omit arguments between comas.

Therefore answers 1 and 3 are wrong.

static void Main()
{
      Foo(10, dt: DateTime.Now);
      Foo(i2: 10, s: "abc", i1: 5);
}

static void Foo(int i1, int i2 = 0, DateTime dt = default(DateTime), string s = null)
{
      Console.WriteLine("Foo");
}