using System;
public class MyClass : IFormattable
{
private string title;
private string[] names;
public MyClass(string title, params string[] names)
{
this.title = title;
this.names = names;
}
public override string ToString()
{
return ToString("G", null);
}
public string ToString(string format, IFormatProvider formatProvider)
{
string result = null;
if (format == null)
format = "G";
switch (format.ToUpper()[0])
{
case 'S':
result = "S." ;
break;
case 'P':
result = "P. ";
break;
case 'I':
result = "I. ";
break;
case 'G':
default:
result = "G. ";
break;
}
return result;
}
}
public class MainClass
{
public static void Main()
{
MyClass person = new MyClass("Mr", "A", "B", "C", "D");
System.Console.WriteLine("Dear {0:G},", person);
System.Console.WriteLine("Dear {0:P},", person);
System.Console.WriteLine("Dear {0:I},", person);
System.Console.WriteLine("Dear {0},", person);
System.Console.WriteLine("Dear {0:S},", person);
}
}
Dear G. ,
Dear P. ,
Dear I. ,
Dear G. ,
Dear S.,