AppDomain.CreateInstanceFrom Method (String, String, Object)
Creates a new instance of the specified type defined in the specified assembly file.
Assembly: mscorlib (in mscorlib.dll)
public ObjectHandle CreateInstanceFrom( string assemblyFile, string typeName, Object activationAttributes )
- Type: System.String
The name, including the path, of a file that contains an assembly that defines the requested type. The assembly is loaded using the LoadFrom method.
- Type: System.String
The fully qualified name of the requested type, including the namespace but not the assembly, as returned by the Type.FullName property.
Return ValueType: System.Runtime.Remoting.ObjectHandle
An object that is a wrapper for the new instance, or null if typeName is not found. The return value needs to be unwrapped to access the real object.
Implements_AppDomain.CreateInstanceFrom(String, String, Object)
assemblyFile is null.
assemblyFile was not found.
typeName was not found in assemblyFile.
The caller does not have sufficient permission to call this constructor.
No matching public constructor was found.
The caller cannot provide activation attributes for an object that does not inherit from MarshalByRefObject.
The operation is attempted on an unloaded application domain.
assemblyFile is not a valid assembly.
Version 2.0 or later of the common language runtime is currently loaded and assemblyFile was compiled with a later version.
An assembly or module was loaded twice with two different evidences.
This instance is null.
The default constructor for typeName is invoked.
The activationAttributes parameter is related to client-activated objects; see Client Activation.
For more information about this method, see the Activator.CreateInstanceFrom method.
When the CreateInstanceFrom method is used to create an instance in a target application domain, other than the application domain from which the call is made, the assembly is loaded in the target application domain. However, if the instance is unwrapped in the calling application domain, using the unwrapped instance in certain ways can cause the assembly to be loaded into the calling application domain. For example, after the instance is unwrapped, its type information might be requested, in order to call its methods late-bound. When the assembly is loaded into the calling application domain, exceptions can occur.
If another version of the same assembly was previously loaded into the calling application domain, or if the load path of the calling application domain is different from that of the target application domain, exceptions such as MissingMethodException can occur.
If the calling application domain makes early-bound calls to the instance type, InvalidCastException can be thrown when an attempt is made to cast the instance.
for the ability to access the location of the assembly. Associated enumeration: FileIOPermissionAccess.PathDiscovery
for the ability to read the file containing the assembly manifest. Associated enumeration: FileIOPermissionAccess.Read
for the ability to access the location of the assembly if the assembly is not local.