How to create a new object instance from a Type

c# .net performance reflection types
tags2k picture tags2k · Aug 3, 2008 · Viewed 551.7k times · Source

One may not always know the Type of an object at compile-time, but may need to create an instance of the Type.

How do you get a new object instance from a Type?

Answer

Karl Seguin picture Karl Seguin · Aug 3, 2008

The Activator class within the root System namespace is pretty powerful.

There are a lot of overloads for passing parameters to the constructor and such. Check out the documentation at:

http://msdn.microsoft.com/en-us/library/system.activator.createinstance.aspx

or (new path)

https://docs.microsoft.com/en-us/dotnet/api/system.activator.createinstance

Here are some simple examples:

ObjectType instance = (ObjectType)Activator.CreateInstance(objectType);

ObjectType instance = (ObjectType)Activator.CreateInstance("MyAssembly","MyNamespace.ObjectType");

Related questions

How costly is .NET reflection?

I constantly hear how bad reflection is to use. While I generally avoid reflection and rarely find situations where it is impossible to solve my problem without it, I was wondering... For those who have used reflection in applications, have …

Read More
Best way to reverse a string

I've just had to write a string reverse function in C# 2.0 (i.e. LINQ not available) and came up with this: public string Reverse(string text) { char[] cArray = text.ToCharArray(); string reverse = String.Empty; for (int i = cArray.Length - 1; …

Read More
What's the fastest way to read a text file line-by-line?

I want to read a text file line by line. I wanted to know if I'm doing it as efficiently as possible within the .NET C# scope of things. This is what I'm trying so far: var filestream = new System.…

Read More