C#中Dictionary类使用实例

//************************************************************ 
// 
// Dictionary示例代码 
// 
// Author：三五月儿 
//  
// Date：2014/09/14 
// 
// 
//************************************************************ 
using System;
using System.Collections.Generic;
using System.Linq;
namespace DictionaryExp
{
  class Program
  {
    static void Main(string[] args)
    {
      //所有班级所有学生成绩报告单
      Dictionary<int, List<ScoreReport>> scoreDictionary = new Dictionary<int, List<ScoreReport>>();
      //将1班所有学生成绩加入字典
      scoreDictionary.Add(1,
        new List<ScoreReport>()
        {
          new ScoreReport(){Name="三五月儿",ChineseScore=100,MathScore=100,EnglishScore=100},
          new ScoreReport(){Name="张三",ChineseScore=80,MathScore=78,EnglishScore=91},
          new ScoreReport(){Name="李四",ChineseScore=90,MathScore=87,EnglishScore=88}
        });
      //将2班所有学生的成绩加入字典
      scoreDictionary.Add(2,
        new List<ScoreReport>()
        {
          new ScoreReport(){Name="王五",ChineseScore=78,MathScore=88,EnglishScore=98},
          new ScoreReport(){Name="丁六",ChineseScore=77,MathScore=99,EnglishScore=91},
          new ScoreReport(){Name="魏源",ChineseScore=45,MathScore=66,EnglishScore=99}
        });
      //将3班所有学生的成绩加入字典
      scoreDictionary.Add(3,
        new List<ScoreReport>()
        {
          new ScoreReport(){Name="周鹏",ChineseScore=99,MathScore=89,EnglishScore=78},
          new ScoreReport(){Name="毛钱",ChineseScore=66,MathScore=98,EnglishScore=91},
          new ScoreReport(){Name="皮蛋",ChineseScore=87,MathScore=69,EnglishScore=88}
        });
 
      //所有班级学生成绩统计报告单
      Dictionary<int, ScoreStatistics> scoreStatisticsDictionary = new Dictionary<int, ScoreStatistics>();
      scoreStatisticsDictionary.Add(1, new ScoreStatistics());
      scoreStatisticsDictionary.Add(2, new ScoreStatistics());
      scoreStatisticsDictionary.Add(3, new ScoreStatistics());
 
      //获取班级Key的集合
      Dictionary<int, List<ScoreReport>>.KeyCollection keyCollection = scoreDictionary.Keys;
      //通过班级Key遍历班级学生成绩
      foreach (var key in keyCollection)
      {
        //班级成绩统计报告单中包含本班级时才继续
        if (scoreStatisticsDictionary.ContainsKey(key))
        {
          //当前班级所有学生的详细成绩报告单
          List<ScoreReport> scoreList = new List<ScoreReport>();
          scoreDictionary.TryGetValue(key, out scoreList);          
          if (scoreList != null && scoreList.Count > 0)
          {//当前班级所有学生的详细成绩报告单中存在数据
            int count = scoreList.Count;//当前班级学生人数
            //生成当前班级学生成绩的统计报告单
            ScoreStatistics scoreStatistics = new ScoreStatistics();
            scoreStatisticsDictionary.TryGetValue(key, out scoreStatistics);
            scoreStatistics.ClassId = key;
            scoreStatistics.TotalChineseScore = scoreList.Sum(it => it.ChineseScore);
            scoreStatistics.TotalMathScore = scoreList.Sum(it => it.MathScore);
            scoreStatistics.TotalEnglishScore = scoreList.Sum(it => it.EnglishScore);
            scoreStatistics.AverageChineseScore = scoreStatistics.TotalChineseScore / count;
            scoreStatistics.AverageMathScore = scoreStatistics.TotalMathScore / count;
            scoreStatistics.AverageEnglishScore = scoreStatistics.TotalEnglishScore / count;
          }
        }
      }
 
      foreach (var s in scoreStatisticsDictionary)
      {
        Console.WriteLine("ClassId = {0},TotalChineseScore = {1},TotalMathScore = {2},TotalEnglishScore = {3},AverageChineseScore = {4},AverageMathScore = {5},AverageEnglishScore = {6}",
          s.Value.ClassId, s.Value.TotalChineseScore, s.Value.TotalMathScore, s.Value.TotalEnglishScore, s.Value.AverageChineseScore, s.Value.AverageMathScore, s.Value.AverageEnglishScore);
        Console.WriteLine("-------------------------------------------------");
      }
    }
  }
  class ScoreReport
  {
    public string Name { get; set; }
    public int ChineseScore { get; set; }
    public int MathScore { get; set; }
    public int EnglishScore { get; set; }
  }
 
  class ScoreStatistics
  {
    public int ClassId { get; set; }
    public int TotalChineseScore { get; set; }
    public int TotalMathScore { get; set; }
    public int TotalEnglishScore { get; set; }
    public int AverageChineseScore { get; set; }
    public int AverageMathScore { get; set; }
    public int AverageEnglishScore { get; set; }
  }
}