給我使用字符串

Question

纔看到的這裏反射的幾個實例對象的屬性，但不能似乎讓他們爲我的確切問題工作...

example of a solution I looked at

我的3個班...

public class Row 
    { 
     public string Cell1 = "cat";//{ get; set; } 
     public string Cell2 = "fish"; //{ get; set; } 
     public string Cell3 = "dog"; //{ get; set; } 


    } 

    public class Grid 
    { 
     public Row Row1 = new Row(); 
     public Row Row2 = new Row(); 
     public Row Row3 = new Row(); 

    } 

    public class SetOfGrids 
    { 
     public Grid g1 = new Grid(); 
     public Grid g2 = new Grid(); 
    } 

我怎樣才能獲得價值...

SetOfGrids sog = new SetOfGrids(); 
MessageBox.Show(sog.g1.Row1.Cell1); 

使用getProperty本功能離子因爲我覺得可能工作的鏈接...

public Object GetPropValue(String name, Object obj) { 
    foreach (String part in name.Split('.')) { 
     if (obj == null) { return null; } 

     Type type = obj.GetType(); 
     PropertyInfo info = type.GetProperty(part); 
     if (info == null) { return null; } 

     obj = info.GetValue(obj, null); 
    } 
    return obj; 
} 

我如何想獲得的價值...（我得到一個空異常錯誤。）

string PathToProperty = "sog.g1.Row1.Cell1"; 
string s = GetPropValue(PathToProperty, sog).ToString; 
MessageBox.Show(s); 

的結果應該是「CAT2 「

更新將行代碼更改爲建議的以下內容。

public class Row 
    { 
     public string Cell1 { get; set; } 
     public string Cell2 { get; set; } 
     public string Cell3 { get; set; } 
     public Row() 
     { 
      this.Cell1 = "cat"; 
      this.Cell2 = "dog"; 
      this.Cell3 = "fish"; 
     } 

    } 

Answer 1

此：

using System; 
using System.Linq; 
using System.Net; 
using System.Reflection; 

namespace Test 
{ 
    public class Row 
    { 
     public string Cell1 { get; set; } 
     public string Cell2 { get; set; } 
     public string Cell3 { get; set; } 
    } 

    public class Grid 
    { 
     public Row Row1 { get; set; } 
     public Row Row2 { get; set; } 
     public Row Row3 { get; set; } 
    } 

    public class SetOfGrids 
    { 
     public Grid g1 { get; set; } 
     public Grid g2 { get; set; } 
    } 

    class Program 
    { 
     public static object GetPropValue(string name, object obj) 
     { 
      foreach (string part in name.Split('.')) 
      { 
       if (obj == null) { return null; } 

       var type = obj.GetType(); 
       var info = type.GetProperty(part); 

       if (info == null) { return null; } 

       obj = info.GetValue(obj, null); 
      } 

      return obj; 
     } 

     public static void Main() 
     { 
      SetOfGrids sog = new SetOfGrids 
      { 
       g1 = new Grid { Row1 = new Row { Cell1 = "cat", Cell2 = "fish", Cell3 = "dog" }, Row2 = new Row { Cell1 = "cat", Cell2 = "fish", Cell3 = "dog" }, Row3 = new Row { Cell1 = "cat", Cell2 = "fish", Cell3 = "dog" } }, 
       g2 = new Grid { Row1 = new Row { Cell1 = "cat", Cell2 = "fish", Cell3 = "dog" }, Row2 = new Row { Cell1 = "cat", Cell2 = "fish", Cell3 = "dog" }, Row3 = new Row { Cell1 = "cat", Cell2 = "fish", Cell3 = "dog" } } 
      }; 

      string PathToProperty = "g1.Row1.Cell1"; 

      object s = GetPropValue(PathToProperty, sog); 

      Console.WriteLine(s); 
      Console.ReadLine(); 
     } 
    } 
} 

工作正常。請注意，我將所有字段都更改爲實際屬性，並刪除了字符串的第一部分，因爲「sog」。是變量名稱，而不是屬性。

Answer 2

問題是你問方法GetProperty讓你的字段，而不是屬性。嘗試將字段更改爲屬性或使用GetField方法。