初见继承威力

我们来描述一个数据结构，一个公司，下有很多部门，一个部门有很多职员。

ok，我们先实现职员数据结构

1

public class Staff
2





{
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//默认为男性
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public Staff(string name):this(name,Sex.Man)
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{
6

}
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public Staff(string name,Sex sex)
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{
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Name = name;
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Sex = sex;
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}
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public readonly string Name;
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public readonly Sex Sex;
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}
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public enum Sex
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{
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Man,
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Female
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}
then, 我们再来处理职员的集合

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public class StaffCollection : System.Collections.CollectionBase
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{
3


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public int Add(string name)
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{
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return Add(name, Sex.Man);
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}
8


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public int Add(string name, Sex sex)
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{
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return Add(new Staff(name, sex));
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}
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public int Add(Staff staff)
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{
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return this.List.Add(staff);
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}
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public void AddRange(Staff[] staffs)
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{
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for (int i = 0; i <= staffs.Length - 1; i++)
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{
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Add(staffs[i]);
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}
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}
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public void Remove(Staff staff)
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{
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this.List.Remove(staff);
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}
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public Staff[] ToArray()
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{
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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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{
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tmpStaffs[i] = (Staff)this[i];
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}
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return tmpStaffs;
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}
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public Staff this[int index]
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{
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set
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{
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this.List[index] = value;
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}
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get
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{
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return (Staff)this.List[index];
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}
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}
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}

我们再定义部门的数据结构，该结构包含了职员的集合

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public class Department
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{
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public StaffCollection Staffs=new StaffCollection();
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public Department(string name)
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{
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Name=name;
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}
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public readonly string Name;
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}

再对StaffCollection依葫芦画瓢，再写一个DepartmentCollection

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public class DepartmentCollection : System.Collections.CollectionBase
2





{
3

public int Add(string departmentName)
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{
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return Add(new Department(departmentName));
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}
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public int Add(Department department)
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{
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return this.List.Add(department);
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}
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public void AddRange(Department[] departments)
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{
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for (int i = 0; i <= departments.Length - 1; i++)
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{
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Add(departments[i]);
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}
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}
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public void Remove(Department department)
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{
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this.List.Remove(department);
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}
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public Department[] ToArray()
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{
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Department[] tmpDepartments = new Department[this.Count];
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for (int i = 0; i <= this.Count - 1; i++)
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{
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tmpDepartments[i] = (Department)this[i];
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}
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return tmpDepartments;
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}
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public Department this[int index]
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{
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set
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{
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this.List[index] = value;
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}
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get
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{
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return (Department)this.List[index];
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}
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}
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}

注意观察DepartmentCollection和StaffCollection的ToArray方法，封装了ToArray复杂性。

最后，我们实现公司的结构

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public class Company
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{
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public DepartmentCollection Departments = new DepartmentCollection();
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}

现在我们有了5个类
Company
---DepartmentCollection
------Department
---------StaffCollection
------------Staff

我们看下具体的应用

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public static void Main(string[] args)
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{
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Company com = new Company();
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com.Departments.Add("HR");
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com.Departments.Add("Market");
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com.Departments.Add("Development");
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com.Departments[0].Staffs.Add("Alice");
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com.Departments[0].Staffs.Add("Amy");
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com.Departments[0].Staffs.Add("Ellen");
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com.Departments[2].Staffs.Add("Albert");
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com.Departments[2].Staffs.Add("Mark");
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com.Departments[2].Staffs.Add("Kevin");
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com.Departments[2].Staffs.Add("Neil");
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for (int i = 0; i <= com.Departments.Count - 1; i++)
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{
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System.Console.WriteLine(com.Departments[i].Name);
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for (int j = 0; j <= com.Departments[i].Staffs.Count - 1; j++)
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{
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System.Console.WriteLine("/t{0}{1}", com.Departments[i].Staffs[j].Name, com.Departments[i].Staffs[j].Sex == Sex.Man ? "先生" : "女士");
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}
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}
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}

继续优化，请看下篇，索引器的重载