CustomActivator

Is a very simple C# .NET library that is able to create a proxy to an interface at runtime, implementing their properties with the default values or custom values passed by parameter.

How it works

It creates an ExpandoObject at runtime and uses the impromptu-interface to make it "Act Like" an interface.

How to Use

Given you have this interface

public interface IParametersTest
{
    int Integer { get; set; }
    bool Boolean { get; set; }
    int AnotherInteger { get; set; }
    bool AnotherBoolean { get; set; }
    int? IntegerNullable { get; set; }
}

You can instantiate a dynamic object that implements this interface by simply calling:

CustomActivator.CreateInstance<IParametersTest>();

It will return the instance of an object that implements the interface and each property will have its default value.

Note: The call to CustomActivator.CreateInstance<> works with classes too (not only interfaces!). So if you pass a class, it just calls the default Ativator.CreateInstance<> from the .NET Framework.

Other Features

Instantiate with custom values

You can also call it passing a Dictionary<string, object> as parameter to set values to the properties:

var properties = new Dictionary<string, object>();
properties.Add("Integer", 30);
properties.Add("Boolean", true);
properties.Add("AnotherInteger", "99"); //Passing with incorrect type works to ;D
properties.Add("AnotherBoolean", "true");
//properties.Add("IntegerNullable", "200"); //We dont want to pass it

var resultObject = CustomActivator.CreateInstance<IParametersTest>(properties);
resultObject.Integer.Should().Be(30);
resultObject.Boolean.Should().Be(true);
resultObject.AnotherInteger.Should().Be(99);
resultObject.AnotherBoolean.Should().Be(true);
resultObject.IntegerNullable.Should().Be(null); //default value!

Setting properties to an existing object

Only call it again passing a Dictionary<string, object>

var myObject = new InstantiableObject();
myObject.Integer = 1;
myObject.Boolean = false;
myObject.AnotherInteger = 2;
myObject.AnotherBoolean = false;
myObject.IntegerNullable = 3;

var properties = new Dictionary<string, object>();
//properties.Add("Integer", "10");
properties.Add("Boolean", "true");
properties.Add("AnotherInteger", "20");
properties.Add("AnotherBoolean", "true");
properties.Add("IntegerNullable", null);

CustomActivator.PopulateObjectProperties(myObject, properties);

myObject.Integer.Should().Be(1);
myObject.Boolean.Should().Be(true);
myObject.AnotherInteger.Should().Be(20);
myObject.AnotherBoolean.Should().Be(true);
myObject.IntegerNullable.Should().Be(null);

That's it :)