七、C# 接口

 1     class Program
 2     {
 3         static void Main(string[] args)
 4         {
 5  
 6             IListTable i;
 7             Contact c = new Contact();
 8             c.Name = "name1";
 9             Console.WriteLine(c.ColnumName);
10  
11             Appointment a = new Appointment();
12             a.Name = "name2";
13             Console.WriteLine(((IListTable)a).ColnumName);
14  
15             Console.ReadLine();
16  
17         }
18     }
19  
20     interface IListTable
21     {
22         string ColnumName
23         { get; }
24     }
25     public class Contact : IListTable
26     {
27         public string Name
28         {
29             get
30             {
31                 return FirtstName;
32             }
33             set
34             {
35                 FirtstName = value + " from Contact";
36             }
37         }
38         private string FirtstName;
39         //隐式实现
40         public string ColnumName
41         {
42             get { return FirtstName + " ColnumName"; }
43             set { FirtstName = value; }
44         }
45  
46  
47     }
48     public class Appointment : IListTable
49     {
50         public string Name
51         {
52             get
53             {
54                 return FirtstName;
55             }
56             set
57             {
58                 FirtstName = value + " from Appointment";
59             }
60         }
61         private string FirtstName;
62  
63         //显式实现
64         string IListTable.ColnumName
65         {
66             get { return FirtstName + " ColnumName"; }
67             //set { FirtstName = value; }//错误
68         }
69  
70     }

 1      class Program
 2     {
 3         static void Main(string[] args)
 4         {
 5  
 6  
 7         }
 8     }
 9  
10     public interface IReadAbleSettingsProvider
11     {
12         string GetSetting(string name, string defaultValue);
13     }
14     public interface ISettingsProvider : IReadAbleSettingsProvider
15     {
16         void SetSetting(string name, string value);
17     }
18     class FileSettingsProvider : ISettingsProvider
19     {
20         public void SetSetting(string name, string value)
21         {
22             //
23         }
24         string IReadAbleSettingsProvider.GetSetting(string name, string defaultValue)
25         {
26             //
27             return " ";
28         }
29     }
30  

 1     class FileSettingsProvider : ISettingsProvider, IReadAbleSettingsProvider
 2     {
 3         public void SetSetting(string name, string value)
 4         {
 5             //
 6         }
 7         string IReadAbleSettingsProvider.GetSetting(string name, string defaultValue)
 8         {
 9             //
10             return " ";
11         }
12     }

 1     class Program
 2     {
 3         static void Main(string[] args)
 4         {
 5  
 6             Contact[] items = new Contact[] { new Contact(), new Contact() };
 7             for (int i = 0; i < items.Length; i++)
 8             {
 9                 items[i].ColnumName = "name" + i;
10             }
11             items.ListColumn();
12  
13  
14  
15             Console.ReadLine();
16  
17         }
18     }
19  
20     interface IListTable
21     {
22         string ColnumName
23         { get; }
24     }
25     public class Contact : IListTable
26     {
27         public string Name
28         {
29             get
30             {
31                 return FirtstName;
32             }
33             set
34             {
35                 FirtstName = value + " from Contact";
36             }
37         }
38         private string FirtstName;
39         //隐式实现
40         public string ColnumName
41         {
42             get { return FirtstName + " ColnumName"; }
43             set { FirtstName = value; }
44         }
45  
46  
47     }
48    
49     static class Listable
50     {
51         public static void ListColumn(this IListTable[] items)
52         {
53             string headers = "";
54             for (int i = 0; i < items.Length; i++)
55             {
56                 headers += items[i].ColnumName + ",";
57             }
58             Console.WriteLine(headers);
59         }
60     }

 1     public class PdaItem
 2     {
 3         public PdaItem()
 4         {
 5         }
 6         public PdaItem(DateTime pLastUpdated)
 7         {
 8  
 9             LastUpdated = pLastUpdated;
10         }
11         public DateTime LastUpdated { set; get; }
12     }
13     interface IPerson
14     {
15          string FirstName { set; get; }
16          string LastName { set; get; }
17     }
18     public class Person : IPerson
19     {
20         public string Address { set; get; }
21         public string Phone { set; get; }
22  
23         public string FirstName { set; get; }
24         public string LastName { set; get; }
25     }
26     //使用聚合(实现继承Person 和 PdaItem 两个类，并将方法和属性放到接口当中
27     public class Contact : PdaItem, IPerson
28     {
29         private Person _Person;
30         public Person person
31         {
32             set
33             {
34                 _Person = value;
35             }
36             get
37             {
38                 return _Person;
39             }
40         }
41         public string FirstName
42         {
43             get
44             {
45                 return _Person.FirstName;
46             }
47             set
48             {
49                 _Person.FirstName = value;
50             }
51         }
52         public string LastName
53         {
54             get
55             {
56                 return _Person.LastName;
57             }
58             set
59             {
60                 _Person.LastName = value;
61             }
62         }
63  
64     }