Does C# support variable argument on method?

Answer 1

Yes. The classic example would be the params object[] args:

//Allows to pass in any number and types of parameters
public static void Program(params object[] args)

or

void Program(string param1, int param2, params double[] otherParams)

Restrictions:
1. They must all be the same type (or of a child type) as is true for arrays as well
2. Only one params keyword is permitted per method
3. It has to be the last parameter.