ExpandoObject in C# 4.0


ExpandoObject it like a expand property in HTML. Microsoft introduces new class ExpandoObject. It's really dynamic object. It is part of DLR (dynamic language runtime).

The ExpandoObject class enables you to add and delete members of its instances at run time and also to set and get values of these members. This class supports dynamic binding, which enables you to use standard syntax like sampleObject.sampleMember instead of more complex syntax like sampleObject.GetAttribute("sampleMember").


Purpose: To create a runtime instance of any type. You can add properties, methods, and events to instances of the ExpandoObject class.


Here we are creating dynamic instance.

dynamic Employee = new ExpandoObject();
Employee.ID = 1;
Employee.Name =
Employee.Salary = 10000;

Nested dynamic instance

Employee.Addess = new ExpandoObject();
Employee.Addess.City =
Employee.Addess.Country =
Employee.Addess.PinCode = 456123;

Bind dynamic Event

Employee.Click += new EventHandler(SampleHandler);
private void SampleHandler(object sender, EventArgs e)
    //throw new NotImplementedException();

Pass parameter as dynamic.
public void Write(dynamic employee)
    //you can write your logic

Happy coding