Activator.CreateInstance Method (Type, Object[])


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Creates an instance of the specified type using the constructor that best matches the specified parameters.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

public static object CreateInstance(
	Type type,
	params object[] args


Type: System.Type

The type of object to create.

Type: System.Object[]

An array of arguments that match in number, order, and type the parameters of the constructor to invoke. If args is an empty array or null, the constructor that takes no parameters (the default constructor) is invoked.

Return Value

Type: System.Object

A reference to the newly created object.

Exception Condition

type is null.


type is not a RuntimeType.


type is an open generic type (that is, the ContainsGenericParameters property returns true).


type cannot be a TypeBuilder.


Creation of TypedReference, ArgIterator, Void, and RuntimeArgumentHandle types, or arrays of those types, is not supported.


The assembly that contains type is a dynamic assembly that was created with AssemblyBuilderAccess.Save.


The constructor that best matches args has varargs arguments.


The constructor being called throws an exception.


In the .NET for Windows Store apps or the Portable Class Library, catch the base class exception, MemberAccessException, instead.

The caller does not have permission to call this constructor.


Cannot create an instance of an abstract class, or this member was invoked with a late-binding mechanism.


The COM type was not obtained through GetTypeFromProgID or GetTypeFromCLSID.


In the .NET for Windows Store apps or the Portable Class Library, catch the base class exception, MissingMemberException, instead.

No matching public constructor was found.


type is a COM object but the class identifier used to obtain the type is invalid, or the identified class is not registered.


type is not a valid type.

The constructor to be invoked must be accessible and must provide the most specific match with the specified argument list.


Starting with the .NET Framework 2.0 Service Pack 1, this method can be used to access nonpublic types if the caller has been granted ReflectionPermission with the ReflectionPermissionFlag.RestrictedMemberAccess flag and if the grant set of the assembly that contains the nonpublic types is restricted to the caller’s grant set or to a subset thereof. (See Security Considerations for Reflection.)

To use this functionality, your application should target the .NET Framework 3.5 or later.

The following example calls the CreateInstance(Type, Object[]) method to create a String object. It calls the String.String(Char[], Int32, Int32) constructor to instantiate a string that contains ten elements from a character array starting at the fourteenth position.

using System;

public class Example
   public static void Main()
      // Initialize array of characters from a to z.
      Char[] chars = new Char[26]; 
      for (int ctr = 0; ctr < 26; ctr++)
         chars[ctr] = (char) (ctr + 0x0061);

      Object obj = Activator.CreateInstance(typeof(String),
                                            new Object[] { chars, 13, 10 } );
// The example displays the following output:
//       nopqrstuvw

The following example creates a jagged array whose elements are arguments to be passed to a String constructor. The example then passes each array to the CreateInstance(Type, Object[]) method to invoke the appropriate string constructor.

using System;

public class Example
   public static void Main()
      char[] characters = { 'a', 'b', 'c', 'd', 'e', 'f' };
      object[][] arguments = new object[3][] { new object[] { characters },
                                               new object[] { characters, 1, 4 },
                                               new object[] { characters[1], 20 } };

      for (int ctr = 0; ctr <= arguments.GetUpperBound(0); ctr++) {
         object[] args = arguments[ctr];
         object result = Activator.CreateInstance(typeof(String), args);
         Console.WriteLine("{0}: {1}", result.GetType().Name, result);
// The example displays the following output:
//    String: abcdef
//    String: bcde
//    String: bbbbbbbbbbbbbbbbbbbb


for the ability to call unmanaged code when creating an instance of a delegate. Associated enumeration: SecurityPermissionFlag.UnmanagedCode


for accessing a nonpublic type when the grant set of the nonpublic type is restricted to the caller's grant set or to a subset thereof. Associated enumeration: ReflectionPermissionFlag.RestrictedMemberAccess


for accessing nonpublic types regardless of their grant set. Associated enumeration: ReflectionPermissionFlag.MemberAccess

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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