Question

根据“界面隔离原则”我有

{"name": "8808", "ip": "192.168.241.110", "cameras": {"front": ["nf091"], "inside": ["nf067"], "right": ["004317"], "rear": ["000189"], "left": ["nf084"]}, "serial":     "000002", "simId": 197078302}
{"name": "8893", "ip": "192.168.241.137", "cameras": {"front": ["nf052"], "inside": ["000211"], "right": ["000069"], "rear": ["000441"], "left": ["000400"]}, "serial":     "000277", "simId": 197057802}
{"name": "1620", "ip": "192.168.242.145", "cameras": {"front": ["000174"], "inside": ["000197"], "right": ["000304"], "rear": ["000295"], "left": ["000553"]}, "serial":     "000084", "simId": 310922501}
{"name": "0632", "ip": "192.168.242.166", "cameras": {"front": ["nf050"], "inside": ["nf022"], "right": ["nf047"], "rear": ["ne056"], "left": ["ne083"]}, "serial":     "NF016", "simId": 310897301}
{"name": "1544", "ip": "192.168.242.234", "cameras": {"front": ["000061"], "inside": ["000068"], "right": ["004440"], "rear": ["000219"], "left": ["005516"]}, "serial":     "000200", "simId": 310839901}
{"name": "12HA", "ip": "192.168.243.116", "cameras": {"front": ["000625"], "right": ["nf104"], "rear": ["ne047"], "left": ["000717"]}, "serial": "000181", "simId":     510339201}

现在我有一个简单的例子：

interface IMessage
{
   void Send();
   string ToAddress { get; set; }
   string FromAddress { get; set; }
}

interface ITextMessage : IMessage
{
   string Text { get; set; }
}

interface IEmailMessage : ITextMessage
{
   string Subject { get; set; }
}


class EmailMessage : IEmailMessage
{
   public string Text { get; set; }
   public string Subject { get; set; }
   public string FromAddress { get; set; }
   public string ToAddress { get; set; }

   public EmailMessage(string text, string subject /*more parameters*/)
   {
    Text = text; 
    Subject = subject;
    //other parameters
   }

   public void Send()
   {
     Console.WriteLine("Send Email : {0}", Text);
   }
}

class SmsMessage : ITextMessage
{
  public string Text { get; set; }
  public string FromAddress { get; set; }
  public string ToAddress { get; set; }

  public SmsMessage(string text /*more parameters*/)
  {
    Text = text; 
    //other parameters
  }

  public void Send()
  {
     Console.WriteLine("Send Sms : {0}", Text);
  }
}

如何在没有将项目转换为EmailMessage的Messages [1]项目中获取“主题”属性（例如）？我应该使用哪种模式？

Answer 1

这是一个多态问题。

将Subject放在IMessage上，如果没有，则返回null（您也可以提供HasSubject属性），否则需要施放。< / p>

没有对错。如果您不希望IMessage知道Subjects，那么您不希望在那里拥有这样的属性。如果有很多不同的子接口和子类型，那么转换可能会更好。

如何在ViewModel中不使用“接口隔离原则”获取属性

1 个答案: