//引入命名空间
using System;
using System.Numerics;

public class Example
{
   public static void Main()
   {
      // Create a complex number by calling its class constructor.
      Complex c1 = new Complex(12, 6);
      Console.WriteLine(c1);
      
      // Assign a Double to a complex number.
      Complex c2 = 3.14;
      Console.WriteLine(c2);
      
      // Cast a Decimal to a complex number.
      Complex c3 = (Complex) 12.3m;
      Console.WriteLine(c3);
      
      // Assign the return value of a method to a Complex variable.
      Complex c4 = Complex.Pow(Complex.One, -1);
      Console.WriteLine(c4);
      
      // Assign the value returned by an operator to a Complex variable.
      Complex c5 = Complex.One + Complex.One;
      Console.WriteLine(c5);

      // Instantiate a complex number from its polar coordinates.
      Complex c6 = Complex.FromPolarCoordinates(10, .524);
      Console.WriteLine(c6);
   }
}

Complex value = new Complex(Double.MinValue/2, Double.MinValue/2);
Complex value2 = Complex.Exp(Complex.Log(value));
Console.WriteLine("{0} \n{1} \nEqual: {2}", value, value2, 
                                            value == value2);

//引入命名空间
using System;
using System.Numerics;

public class Example
{
   public static void Main()
   {
      Complex c1 = new Complex(Double.MaxValue / 2, Double.MaxValue /2);

      Complex c2 = c1 / Complex.Zero;
      Console.WriteLine(c2.ToString());
      c2 = c2 * new Complex(1.5, 1.5);
      Console.WriteLine(c2.ToString());
      Console.WriteLine();
      
      Complex c3 = c1 * new Complex(2.5, 3.5);
      Console.WriteLine(c3.ToString());
      c3 = c3 + new Complex(Double.MinValue / 2, Double.MaxValue / 2); 
      Console.WriteLine(c3);
   }
}

//引入命名空间
using System;
using System.Numerics;

public class ComplexFormatter :IFormatProvider, ICustomFormatter
{
   public object GetFormat(Type formatType) 
   {   
      if (formatType == typeof(ICustomFormatter))
         return this;
      else
         return null;
   }
   
   public string Format(string format, object arg, 
                        IFormatProvider provider)
   {
      if (arg is Complex)
      {
         Complex c1 = (Complex) arg; 
         // Check if the format string has a precision specifier.
         int precision;
         string fmtString = String.Empty;
         if (format.Length > 1) {
            try {
               precision = Int32.Parse(format.Substring(1));
            }
            catch (FormatException) {
               precision = 0;
            }
            fmtString = "N" + precision.ToString();
         }
         if (format.Substring(0, 1).Equals("I", StringComparison.OrdinalIgnoreCase))
            return c1.Real.ToString(fmtString) + " + " + c1.Imaginary.ToString(fmtString) + "i";
         else if (format.Substring(0, 1).Equals("J", StringComparison.OrdinalIgnoreCase))
            return c1.Real.ToString(fmtString) + " + " + c1.Imaginary.ToString(fmtString) + "j";
         else
            return c1.ToString(format, provider);
      }
      else
      {
         if (arg is IFormattable)
            return ((IFormattable) arg).ToString(format, provider);
         else if (arg != null) 
            return arg.ToString();
         else
            return String.Empty;
      }                        
   }
}

public class Example
{
   public static void Main()
   {
      Complex c1 = new Complex(12.1, 15.4);
      Console.WriteLine("Formatting with ToString():       " + 
                        c1.ToString());
      Console.WriteLine("Formatting with ToString(format): " + 
                        c1.ToString("N2"));
      Console.WriteLine("Custom formatting with I0:        " + 
                        String.Format(new ComplexFormatter(), "{0:I0}", c1));
      Console.WriteLine("Custom formatting with J3:        " + 
                        String.Format(new ComplexFormatter(), "{0:J3}", c1));
   }
}