Activator.CreateInstanceFrom Method (String, String)
Assembly: mscorlib (in mscorlib.dll)
public static function CreateInstanceFrom ( assemblyFile : String, typeName : String ) : ObjectHandle
The name of a file that contains an assembly where the type named typeName is sought.
The name of the preferred type.
Return ValueA handle that must be unwrapped to access the newly created instance.
typeName is a null reference (Nothing in Visual Basic).
No matching public constructor was found.
typename was not found in assemblyFile.
assemblyFile 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 caller does have the required FileIOPermission.
assemblyFile 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.
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 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)
- SecurityPermission for the ability to call unmanaged code when creating an instance of a delegate. Associated enumeration: SecurityPermissionFlag.UnmanagedCode
- FileIOPermission for the ability to search directory paths and read their contents. Associated enumerations: FileIOPermissionAccess.PathDiscovery and FileIOPermissionAccess.Read
- ReflectionPermission for accessing nonpublic types when the grant set of the nonpublic types is restricted to the caller's grant set, or to a subset thereof. Associated enumeration: System.Security.Permissions.ReflectionPermissionFlag.RestrictedMemberAccess
- ReflectionPermission for accessing nonpublic types regardless of their grant set. Associated enumeration: ReflectionPermissionFlag.MemberAccess
Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter EditionThe Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.