.NET Framework Standard Library Annotated Reference, Volume 1: Base Class Library and Extended Numerics Library

Example

using System;

namespace Samples
{
  public class IFormattableSample
  {
    public static void Main()
    {
      double d = 123.12345678901234;
      string[] strings = {"C","E","e","F","G","N","P","R"};
      foreach(string s in strings)
        Console.WriteLine("{0:R} as {1}: {2}",
                          d, s, d.ToString(s,null));
      strings = new string[]{"D","x","X"};
      int i = 255;
      foreach(string s in strings)
        Console.WriteLine("{0} as {1}: {2}",
                          i, s, i.ToString(s,null));
    }
  }
}

The output is

 123.12345678901234 as C: $123.12 123.12345678901234 as c: $123.12 123.12345678901234 as E: 1.231235E+002 123.12345678901234 as e: 1.231235e+002 123.12345678901234 as F: 123.12 123.12345678901234 as G: 123.123456789012 123.12345678901234 as g: 123.123456789012 123.12345678901234 as N: 123.12 123.12345678901234 ...