c# 3.0 new features Example Demo

   1:  /////////////////////////////////////////////////////

   2:  //

   3:  // 總結所有的 New Features(language extensions)

   4:  //

   5:  /////////////////////////////////////////////////////

   6:   

   7:  using System;

   8:  using System.Collections.Generic;

   9:  using System.Linq;

  10:  using System.Text;

  11:  using System.Diagnostics;

  12:   

  13:  static class newFeaturesDemo

  14:  {

  15:      class ProcessData {

  16:          public Int32 Id { set; get; }

  17:          public Int64 Memory { set; get; }

  18:          public String Name { set; get; }

  19:      }

  20:   

  21:      public static void DisplayProcesses(Func<Process, Boolean> match) {

  22:          

  23:          // 1. implicitly typed local variables

  24:          var processes = new List<ProcessData>();

  25:   

  26:          foreach (var process in Process.GetProcesses()) {

  27:              if (match(process)) {

  28:                  

  29:                  // 2. object initialized

  30:                  processes.Add(new ProcessData

  31:                  {

  32:                      Id = process.Id,

  33:                      Name = process.ProcessName,

  34:                      Memory = process.WorkingSet64

  35:                  });

  36:              }

  37:          }

  38:   

  39:          // 3. extension methods

  40:          Console.WriteLine("Total memeory: {0} MB",

  41:                             processes.TotalMemory()/1024/1024);

  42:   

  43:          // 4. lambda expression

  44:          var top2Memory = processes

  45:                           .OrderByDescending(process => process.Memory)

  46:                           .Take(2)

  47:                           .Sum(process => process.Memory) / 1024 / 1024;

  48:   

  49:          Console.WriteLine(

  50:              "Memory consumed by the two most hungry processes: {0} MB",

  51:              top2Memory);

  52:   

  53:          // 5. anonymous type

  54:          var results = new

  55:          {

  56:              TotalMemory = processes.TotalMemory() / 1024 / 1024,

  57:              Top2Memory = top2Memory,

  58:              Processes = processes

  59:          };

  60:          

  61:          ObjectDumper.Write(results, 1);

  62:          ObjectDumper.Write(processes);

  63:   

  64:      }

  65:   

  66:      static Int64 TotalMemory(this IEnumerable<ProcessData> processes) {

  67:          Int64 result = 0;

  68:          foreach (var process in processes) {

  69:              result += process.Memory;

  70:          }

  71:   

  72:          return result;

  73:      }

  74:   

  75:    static void Main()

  76:    {

  77:      DisplayProcesses(

  78:        process => process.WorkingSet64 >= 20*1024*1024);

  79:    }     

  80:  }