如何從主類循環子類屬性？

Question

如何從主類循環子類屬性？

public class GroupA 
{ 
    public string FullName = "", BirthDay = ""; 
} 
public class GroupB 
{ 
    public string Email = ""; 
} 
public class GroupC 
{ 
    public string Phone; 
} 

public class MainGroup 
{ 
    public GroupA GroupA; 
    public GroupB GroupB; 
    public GroupC GroupC; 
} 


    protected void Page_Load(object sender, EventArgs e) 
    { 

     GroupA NewGroupA = new GroupA(); 
       NewGroupA.FullName="TEST MASTER"; 
       NewGroupA.BirthDay="02/20/1984"; 
     GroupB NewGroupB = new GroupB(); 
       NewGroupB.Email="noreply@test.com"; 
     GroupC NewGroupC=new GroupC(); 
       NewGroupC.Phone="555 123 4567"; 

     //Assign new class instances to the main class 
     MainGroup NewMainGroup= new MainGroup(); 
       NewMainGroup.GroupA=NewGroupA; 
       NewMainGroup.GroupB=NewGroupB;     
       NewMainGroup.GroupC=NewGroupC; 

     //Loop through the main class 

     foreach (var Group in typeof(MainGroup).GetFields()) 
     { 
     Response.Write("<BR>MainGroupName= " + Group.Name + " Value= " + Group.GetValue(NewMainGroup).ToString()); 
     //PROBLEM IS HERE. Can't loop through the subclass We need to display the GroupA, GroupB, GroupC below. 
     foreach (var SubGroup in Group) 
     { 
      Response.Write("<BR>"); 
     } 


     } 
} 

Answer 1

你應該如何存儲對組變量的引用（不僅僅是類型）。所以，如果你拿你的代碼，並做這樣的事情：

foreach (var GroupType in typeof(MainGroup).GetFields()) 
{ 
    object Group = GroupType.GetValue(NewMainGroup); 
    Response.Write("<BR>MainGroupName= " + GroupType.Name + " Value= " + Group.ToString()); 
    foreach(var SubGroupType in Group.GetType().GetFields()) { 
     object SubGroup = SubGroupType.GetValue(Group); 
     Response.Write("<BR>SubGroupName= " + SubGroupType.Name + " Value= " + SubGroup.ToString()); 
    } 
} 

沒有測試過，但我認爲這應該工作。至少讓你開始。

哦，順便說一下，我覺得我對你有一個更好的方法，試試這個：

public Dictionary<string, object> GetObjectFields(object obj) { 
    var dict = new Dictionary<string, object>(); 
    var t = obj.GetType(); 
    foreach(var f in t.GetFields()) { 
     dict[f.Name] = f.GetValue(obj); 
    } 
    return dict; 
} 

然後，你可以簡單地這樣做：

var groupVars = GetObjectFields(NewMainGroup); 
foreach(var gv in groupVars) { 
    Response.Write(<BR>MainGroupName= " + gv.Key + " Value= " + gv.Value.ToString()); 
    var subGroupVars = GetObjectFields(gv.Value); 
    foreach(var sgv in subGroupVars) { 
     Response.Write(<BR>SubGroupName= " + sgv.Key + " Value= " + sgv.Value.ToString()); 
    } 
} 

Answer 2

如果我理解你的問題沒錯，我認爲這段代碼是你的答案：

Answer 3

第一件事第一件GroupA，GroupB和GroupC不是MainGroup的子類。 您正在使用組合並擁有GroupA，GroupB和GroupC類型的成員。

不知道當你已經知道你的類型時，爲什麼你要重新選擇類型。 你可以使用MainGroup.GroupA.Name等等。可能是你發佈的代碼只是一個例子？

以下方法應該反映基本結構並適合您的目的。

 static String Reflect(Object data) 
     { 
      StringBuilder stringBuilder = new StringBuilder(); 

      foreach (PropertyInfo propertyInfo in data.GetType().GetProperties()) 
      { 
       if (propertyInfo.PropertyType.IsClass && propertyInfo.PropertyType != typeof(String)) 
       { 
        stringBuilder.AppendFormat("{0} : {1} {2}", propertyInfo.Name, Environment.NewLine 
         , Reflect(propertyInfo.GetValue(data, null))); 
       } 
       else 
       { 
        stringBuilder.AppendFormat("{0} = {1}, {2}", propertyInfo.Name, propertyInfo.GetValue(data, null), Environment.NewLine); 
       } 
      } 

      return stringBuilder.ToString(); 
     } 

用法：

  MainGroup main = new MainGroup 
      { 
       A = new GroupA { Name = "GroupA", ID = 1 }, 
       B = new GroupB { Date = DateTime.UtcNow }, 
       C = new GroupC { HasData = false } 
      }; 

      Reflect(main);