C# How to acces to Values of an class Object, by an another Class object

Question

I want to assign an object of one class to another class by constructor, and retrieve the values of the class assigned by constructor from the class which has the constructor. 听起来令人困惑，它也是:)。 处理不了。 你有什么想法？ 这是一个示例代码。

public class Class1
{
   public class1(int value1)
   {
       Value1 = value1;
   }
   public int Value1 { get;}
}

public class Class2
{
   public object Object1 {get; set;}
}

public class main
{

   Class1 TestClass = new Class1(15);
   Class2 TestClass1 = new Class2();

   public void main()
   {
       TestClass1.Object1 = TestClass();

       //Now I want to this
       Console.WriteLine(TestClass1.Object1.Value1);
       TestClass1.Object1.Value1;   
   }
}

Answer 1

为此，您需要创建该特定类型的属性，而不是使用基本 object 类型，例如：

public class Class2
{
   public Class1 Object1 {get; set;}
}

然后你可以写：

Class1 TestClass = new Class1(15);
Class2 TestClass1 = new Class2();

public void main()
{
   TestClass1.Object1 = TestClass;

   //Now you can do what you wanted
   Console.WriteLine(TestClass1.Object1.Value1);
}

如果你真的想使用 object 类型，那么你需要将 object 转换为它的实际类型，然后你可以在编译时使用这些属性：

public class Class2
{
   public object Object1 {get; set;}
}

现在：

public void main()
{
   TestClass1.Object1 = TestClass;

   Class1 temp =  TestClass1.Object1 as Class1;
   // safe guard in case cast fails 
   if(temp !=null)
   {
      //Now you can do what you wanted
      Console.WriteLine(temp.Value1);
   }
}

Answer 2

Class将其子项存储为object和object没有属性Value1 。

您需要Object1属性或使Class2通用。

铸件

Class1 o1 = new Class1(15);
Class2 o2 = new Class2();

o2.Object1 = o1;

var x = o2.Object1 as Class1;
//If o2.Object1 is not Class1 x will be null.  

Console.WriteLine(x.Value1); 

使Class2通用

public class Class1
{
    public Class1(int value1) { Value1 = value1; }
    public int Value1 { get; set; }
}

public class Class2<T>
{
    public T Object1 { get; set; }
}

public static async Task Main()
{
    var o1 = new Class1(15);
    var o2 = new Class2<Class1>();

    o2.Object1 = o1;

    Console.WriteLine(o2.Object1.Value1);
}

Answer 3

以下方法在构造外部/容器实例时将嵌套实例作为构造函数参数。

        public class Inner
        {
            public Inner(int value)
            {
                Value = value;
            }
            public int Value { get; }
        }

        public class Outer
        {
            public Outer(Inner inner)
            {
                InnerObject = inner;
            }
            public Inner InnerObject { get;}
        }

        public class main
        {       

            static void Main()
            {
                var outer = new Outer(new Inner(10));
                Console.WriteLine(outer.InnerObject.Value);
                var value = outer.InnerObject.Value;
            }
        }

Answer 4

尝试这两种 object 扩展方法来获取和设置值。

用法;

myObject.SetPropertyByName("MyProperty", "MyValue");

var value = myObject.GetPropertyValueByName("MyProperty");

public static class FwExtensions
{
    /// <summary>
    /// Set the value of a property if it exists and you don't have an interface
    /// </summary>
    /// <param name="me"></param>
    /// <param name="propertyName"></param>
    /// <param name="value"></param>
    /// <returns> true if the value was found and set, else false</returns>
    public static bool SetPropertyByName(this object me, string propertyName, object value)
    {
        if (me != null)
        {
            PropertyInfo prop = me.GetType().GetProperty(propertyName, BindingFlags.Public | BindingFlags.Instance);
            if (null != prop && prop.CanWrite)
            {
                prop.SetValue(me, value, null);
                return true;
            }
        }
        return false;
    }

    public static object GetPropertyValueByName(this object me, string propertyName)
    {
        if (me != null)
        {
            PropertyInfo prop = me.GetType().GetProperty(propertyName, BindingFlags.Public | BindingFlags.Instance);
            if (null != prop && prop.CanWrite)
            {
                return prop.GetValue(me);
            }
        }
        return null;
    }
}