CreateInstance Method (AppDomain, String, String, Boolean, BindingFlags, Binder, Object[], CultureInfo, Object[])

Activator.CreateInstance Method (AppDomain, String, String, Boolean, BindingFlags, Binder, Object[], CultureInfo, Object[])

.NET Framework 4.6 and 4.5

Creates an instance of the type whose name is specified in the specified remote domain, using the named assembly and the constructor that best matches the specified parameters.

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

static member CreateInstance : 
        domain:AppDomain *
        assemblyName:string *
        typeName:string *
        ignoreCase:bool *
        bindingAttr:BindingFlags *
        binder:Binder *
        args:Object[] *
        culture:CultureInfo *
        activationAttributes:Object[] -> ObjectHandle


Type: System.AppDomain

The domain where the type named typeName is created.

Type: System.String

The name of the assembly where the type named typeName is sought. If assemblyName is null, the executing assembly is searched.

Type: System.String

The fully qualified name of the preferred type.

Type: System.Boolean

true to specify that the search for typeName is not case-sensitive; false to specify that the search is case-sensitive.

Type: System.Reflection.BindingFlags

A combination of zero or more bit flags that affect the search for the typeName constructor. If bindingAttr is zero, a case-sensitive search for public constructors is conducted.

Type: System.Reflection.Binder

An object that uses bindingAttr and args to seek and identify the typeName constructor. If binder is null, the default binder is used.

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.

Type: System.Globalization.CultureInfo

Culture-specific information that governs the coercion of args to the formal types declared for the typeName constructor. If culture is null, the CultureInfo for the current thread is used.

Type: System.Object[]

An array of one or more attributes that can participate in activation. This is typically an array that contains a single UrlAttribute object that specifies the URL that is required to activate a remote object.

This parameter is related to client-activated objects. Client activation is a legacy technology that is retained for backward compatibility but is not recommended for new development. Distributed applications should instead use Windows Communication Foundation.

Return Value

Type: System.Runtime.Remoting.ObjectHandle

A handle that must be unwrapped to access the newly created instance.

Exception Condition

domain or typeName is null.


No matching constructor was found.


typename was not found in assemblyName.


assemblyName was not found.


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 constructor, which was invoked through reflection, threw an exception.


The COM type was not obtained through GetTypeFromProgID or GetTypeFromCLSID.


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


activationAttributes is not an empty array, and the type being created does not derive from MarshalByRefObject.


The constructor that best matches args has varargs arguments.


assemblyName is not a valid assembly.


The common language runtime (CLR) version 2.0 or later is currently loaded, and assemblyName was compiled for a version of the CLR that is later than the currently loaded version. Note that the .NET Framework versions 2.0, 3.0, and 3.5 all use CLR version 2.0.


An assembly or module was loaded twice with two different evidences.


The assembly name or code base is invalid.

Use CreateInstance when a host needs to execute code in an application domain that has restricted security permissions.

Use ObjectHandle.Unwrap to unwrap the return value.


This method uses SecurityAction.LinkDemand to require the immediate caller to have full trust.


requires full trust for the immediate caller. This member cannot be used by partially trusted or transparent code.


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


for the ability to invoke operations on all type members. Associated enumeration: ReflectionPermissionFlag.MemberAccess

.NET Framework
Available since 4.0
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