Using reflection to create an instance [duplicate]

Question

To create an instance of a class we can do that :

Person p = new Person();

But, I want to pass the name of class dynamicaly with a string like that :

String name = "Human.Person"
name n = new name();

I know this is wrong but I saw that I can use reflection but I didn't understand how can I use it for my case.

Also I've removed the visual studio tag. Please only include relevant tags. — David L
– David L, Commented Mar 9, 2017 at 21:25

EventHorizon · Accepted Answer · 2017-03-09 21:25:58Z

2

You can use Activator.CreateInstance for this scenario.

object person = Activator.CreateInstance(Type.GetType("Human.Person"));

or most commonly using a base class or interface:

IPerson person = (IPerson)Activator.CreateInstance(Type.GetType("Human.Person"));

answered Mar 9, 2017 at 21:25

EventHorizon

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4 Comments

And if I want to open a form like : Class c = new Class(); c.Show(); ?

Your class will inherit from Form, so you can use Form c = (Form)Activator.CreateInstance( ... )

Like that : Form c = (Form)Activator.CreateInstance(Type.GetType("Human.Person"); ? I have a ArgumentNullException

My Bad, an error in my class name. Now it works thx

Liu · Accepted Answer · 2017-03-09 21:40:39Z

1

  Type t = Type.GetType(name); 
  Human.Person p = Activator.CreateInstance(t) as Human.Person;

Updated: Thanks @Dag If Human.person is in another assembly

Type t = a.GetType(name, "assemblyName"); 
Human.Person p = Activator.CreateInstance(t) as Human.Person;

answered Mar 9, 2017 at 21:30

Liu

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You don't need to load it, just add the assembly name to the type name like this "Human.Person,something"

You are right. Thanks