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Activator.CreateInstanceFrom Method (String, String)

Creates an instance of the type whose name is specified, using the named assembly file and default constructor.

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

'Declaration
Public Shared Function CreateInstanceFrom ( _
	assemblyFile As String, _
	typeName As String _
) As ObjectHandle

Parameters

assemblyFile
Type: System.String

The name of a file that contains an assembly where the type named typeName is sought.

typeName
Type: System.String

The name of the preferred type.

Return Value

Type: System.Runtime.Remoting.ObjectHandle
A handle that must be unwrapped to access the newly created instance.

ExceptionCondition
ArgumentNullException

typeName is Nothing.

MissingMethodException

No matching public constructor was found.

TypeLoadException

typename was not found in assemblyFile.

FileNotFoundException

assemblyFile was not found.

MethodAccessException

The caller does not have permission to call this constructor.

MemberAccessException

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

TargetInvocationException

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

SecurityException

The caller does have the required FileIOPermission.

BadImageFormatException

assemblyFile is not a valid assembly.

-or-

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.

Use the ObjectHandle.Unwrap method to unwrap the return value.

For information about other exceptions that can be thrown by invoked methods, see the Exceptions section of the Assembly.LoadFrom and CreateInstance methods.

The following code example demonstrates how to call the CreateInstanceFrom method. This code example is part of a larger example provided for the Activator class.

' Create an instance of the SomeType class that is defined in this assembly. 
Dim oh As System.Runtime.Remoting.ObjectHandle = _
    Activator.CreateInstanceFrom(Assembly.GetEntryAssembly().CodeBase, _
                                 GetType(SomeType).FullName)

' Call an instance method defined by the SomeType type using this object. 
Dim st As SomeType = CType(oh.Unwrap(), SomeType)

st.DoSomething(5)

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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