初見繼承威力

我們來描述一個資料結構，一個公司，下有很多部門，一個部門有很多職員。

ok，我們先實作職員資料結構

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 public class Staff

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 {

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 //預設為男性

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 public Staff(string name):this(name,Sex.Man)

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 }

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 public Staff(string name,Sex sex)

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 Name = name;

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 Sex = sex;

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 public readonly string Name;

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 public readonly Sex Sex;

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 public enum Sex

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 Man,

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 Female

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then, 我們再來處理職員的集合

public class StaffCollection : System.Collections.CollectionBase

 public int Add(string name)

 return Add(name, Sex.Man);

 public int Add(string name, Sex sex)

 return Add(new Staff(name, sex));

 public int Add(Staff staff)

 return this.List.Add(staff);

 public void AddRange(Staff[] staffs)

 for (int i = 0; i <= staffs.Length - 1; i++)

 Add(staffs[i]);

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 public void Remove(Staff staff)

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 this.List.Remove(staff);

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 public Staff[] ToArray()

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 Staff[] tmpStaffs = new Staff[this.Count];

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 for (int i = 0; i <= this.Count - 1; i++)

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 tmpStaffs[i] = (Staff)this[i];

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 return tmpStaffs;

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 public Staff this[int index]

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 set

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 this.List[index] = value;

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 get

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 return (Staff)this.List[index];

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我們再定義部門的資料結構，該結構包含了職員的集合

public class Department

 public StaffCollection Staffs=new StaffCollection();

 public Department(string name)

 Name=name;

再對StaffCollection依葫蘆畫瓢，再寫一個DepartmentCollection

public class DepartmentCollection : System.Collections.CollectionBase

 public int Add(string departmentName)

 return Add(new Department(departmentName));

 public int Add(Department department)

 return this.List.Add(department);

 public void AddRange(Department[] departments)

 for (int i = 0; i <= departments.Length - 1; i++)

 Add(departments[i]);

 public void Remove(Department department)

 this.List.Remove(department);

 public Department[] ToArray()

 Department[] tmpDepartments = new Department[this.Count];

 tmpDepartments[i] = (Department)this[i];

 return tmpDepartments;

 public Department this[int index]

 return (Department)this.List[index];

注意觀察DepartmentCollection和StaffCollection的ToArray方法，封裝了ToArray複雜性。

最後，我們實作公司的結構

 public class Company

 public DepartmentCollection Departments = new DepartmentCollection();

現在我們有了5個類

Company

---DepartmentCollection

------Department

---------StaffCollection

------------Staff

我們看下具體的應用

public static void Main(string[] args)

 Company com = new Company();

 com.Departments.Add("HR");

 com.Departments.Add("Market");

 com.Departments.Add("Development");

 com.Departments[0].Staffs.Add("Alice");

 com.Departments[0].Staffs.Add("Amy");

 com.Departments[0].Staffs.Add("Ellen");

 com.Departments[2].Staffs.Add("Albert");

 com.Departments[2].Staffs.Add("Mark");

 com.Departments[2].Staffs.Add("Kevin");

 com.Departments[2].Staffs.Add("Neil");

 for (int i = 0; i <= com.Departments.Count - 1; i++)

 System.Console.WriteLine(com.Departments[i].Name);

 for (int j = 0; j <= com.Departments[i].Staffs.Count - 1; j++)

 System.Console.WriteLine("/t{0}{1}", com.Departments[i].Staffs[j].Name, com.Departments[i].Staffs[j].Sex == Sex.Man ? "先生" : "女士");

繼續優化，請看下篇，索引器的重載

本文轉自shyleoking 51CTO部落格，原文連結:http://blog.51cto.com/shyleoking/806277