CODEWITHSUNDEEP
c#reflection
John Titor
John Titor

Reputation: 77

Set value of a Nested field in reflection

in my application that uses reflection i have two classes

public class FirstClass
{
   public string someVar;
   public SecondClass second;   
   public FirstClass()
   {
      second = new SecondClass();
   }
} 

public class SecondClass
{
   public string anotherVar;
}

in my main program i have an instance of FirstClass

MainProgram()
{
   Object obj = InstanceOfFirstClass() // reflected instance of first class
}

How do i set the value of anotherVar inside obj?

Upvotes: 2

Views: 3255

Answers (2)

Mike Zboray
Mike Zboray

Reputation: 40838

With public fields, this is relatively simple:

    object obj = InstanceOfFirstClass();
    object second = obj.GetType().GetField("second").GetValue(obj);
    second.GetType().GetField("anotherVar").SetValue(second, "newValue");

If the fields were not public, then you would need to use an overload of GetField that takes a BindingFlags argument with the NonPublic flag set.

In .Net 4, you could just use dynamic:

dynamic obj = InstanceOfFirstClass();
obj.second.anotherVar = "newValue";

Upvotes: 2

srsyogesh
srsyogesh

Reputation: 609

You can find the example which reads the field and set a value of the field via reflection in http://msdn.microsoft.com/en-us/library/6z33zd7h.aspx. In your case it will look like 

    Object myObject = InstanceOfFirstClass() // reflected instance of first class
    Type myType = typeof(FirstClass);
    FieldInfo myFieldInfo = myType.GetField("second", 
        BindingFlags.Public | BindingFlags.Instance); 

    // Change the field value using the SetValue method. 
    myFieldInfo.SetValue(myObject , //myobject is the reflected instance
    value);//value is the object which u want to assign to the field);

Upvotes: 1

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