轉載字典地址：http://blog.csdn.net/aladdinty/article/details/3591789

    相關文章： http://www.360doc.com/content/13/1003/23/14070959_318861279.shtml
              http://www.360doc.com/content/13/1003/23/14070959_318861221.shtml
　　（本文未經過測試）

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    namespace 集合
    {
        class 字典
        {
            public static void Main()
            {
                //字典也稱對映或者雜湊表，主要特點是可以根據鍵快速查詢值，也可以自由刪除新增元素
                //在刪除新增時，不會像列表一樣，移動之後的所有元素，產生記憶體的開銷。
                //.net中提供了幾個字典，可以使用最主要的類是Dictionary<TKey,TValue>
                //這個類與我們上面說的SortedList用法完全一樣，這裡不再多說了。
                //鍵的型別　　
                //用做字典中鍵的型別必須重寫Object類中的GetHashCode()方法,只要字典類需要確定元素的位置，就要呼叫本方法
                //字典內部通過呼叫這個方法的返回值，來計算產生雜湊。。這個演算法不做介紹　，但我要知道，它涉及到素數
                //所以字典的容量是一個素數
                //GetHashCode()方法的實現需要遵循以下幾點
                // 1 相同的物件應總是返回相同的值
                // 2 不同的物件可以返回相同的值
                // 3 應執行得比較快，計算的開銷不大。
                // 4 不能刨出異常
                // 5 應至少使用一個例項欄位
                // 6 雜湊碼值應平均分佈在int可以儲存的整個數字區上
                // 7 雜湊碼最好在物件的生存期中不發生變化
                //提示：　字典的效能取決於GetHashCode()方法的實現程式碼
                
                Dictionary<EmployeeID , Employee> emps = new Dictionary<EmployeeID,Employee>(31) ;
                EmployeeID idAladdin = new EmployeeID( "C7102" ) ;
                Employee aladdin = new Employee( "aladdin" , 5000.00m , idAladdin ) ;
                emps.Add( idAladdin , aladdin ) ;
                Console.WriteLine( aladdin ) ;
                EmployeeID idjacky = new EmployeeID( "C7106" ) ;
                Employee jacky = new Employee( "jacky" , 5000.00m , idjacky ) ;
                emps.Add( idjacky , jacky ) ;
                Console.WriteLine( jacky ) ;
                EmployeeID idzhao = new EmployeeID( "C8102" ) ;
                Employee zhao = new Employee( "zhao" , 5000.00m , idzhao ) ;
                emps.Add( idzhao , zhao ) ;
                Console.WriteLine( zhao ) ;
                EmployeeID idxiaofei = new EmployeeID( "C9102" ) ;
                Employee xiaofei = new Employee( "xiaofei" , 5000.00m , idxiaofei ) ;
                emps.Add( idxiaofei , xiaofei ) ;
                Console.WriteLine( xiaofei ) ;
                EmployeeID iddabi = new EmployeeID( "C7602" ) ;
                Employee dabi = new Employee( "dabi" , 5000.00m , iddabi ) ;
                emps.Add( iddabi , dabi ) ;
                Console.WriteLine( dabi ) ;
                EmployeeID idalong = new EmployeeID( "C7302" ) ;
                Employee along = new Employee( "along" , 5000.00m , idalong ) ;
                emps.Add( idalong , along ) ;
                Console.WriteLine( along ) ;
                EmployeeID idcarl = new EmployeeID( "C7402" ) ;
                Employee carl = new Employee( "carl" , 5000.00m , idcarl ) ;
                emps.Add( idcarl , carl ) ;
                Console.WriteLine( carl ) ;
                EmployeeID idjeff = new EmployeeID( "C7502" ) ;
                Employee jeff = new Employee( "jeff" , 5000.00m , idjeff ) ;
                emps.Add( idjeff , jeff ) ;
                Console.WriteLine( jeff ) ;
                EmployeeID iddenny = new EmployeeID( "C6602" ) ;
                Employee denny = new Employee( "denny" , 5000.00m , iddenny ) ;
                emps.Add( iddenny , denny ) ;
                Console.WriteLine( denny ) ;
                EmployeeID idmatt = new EmployeeID( "C7701" ) ;
                Employee matt = new Employee( "matt" , 5000.00m , idmatt ) ;
                emps.Add( idmatt , matt ) ;
                Console.WriteLine( matt ) ;
                Console.ReadLine() ;
            }
        }
        struct EmployeeID : IEquatable<EmployeeID>
        {
            private readonly char prefix ;
            private readonly int number ;
            public EmployeeID( string id )
            {
                this.prefix = (id.ToUpper())[0] ;
                int numLength = id.Length - 1 ;
                this.number = int.Parse( id.Substring( 1 , numLength > 6 ? 6 : numLength ) ) ;
            }
            public override string ToString()
            {
                return this.prefix.ToString() + string.Format( "{0,6:000000}" , number ) ;
            }
            public override int GetHashCode()
            {
                return ( number ^ number << 16 ) * 0x15051505 ;
            }
            public bool Equals( EmployeeID other )
            {
                return (  other.number == this.number && this.prefix == other.prefix  ) ;
            }
        }
        class Employee
        {
            private string name ;
            private decimal salary ;
            private readonly EmployeeID id ;
            public Employee( string name , decimal salary , EmployeeID id ) 
            {
                this.name = name ;
                this.salary = salary ;
                this.id = id ;
            }
            public override string ToString()
            {
                return string.Format( "{0} : {1,-20} {2:C}" , id.ToString() , name,salary ) ;
            }
        }
    }