MarshalByRefObject Class
Enables access to objects across application domain boundaries in applications that support remoting.
Assembly: mscorlib (in mscorlib.dll)
An application domain is a partition in an operating system process where one or more applications reside. Objects in the same application domain communicate directly. Objects in different application domains communicate either by transporting copies of objects across application domain boundaries, or by using a proxy to exchange messages.
MarshalByRefObject is the base class for objects that communicate across application domain boundaries by exchanging messages using a proxy. Objects that do not inherit from MarshalByRefObject are implicitly marshal by value. When a remote application references a marshal by value object, a copy of the object is passed across application domain boundaries.
MarshalByRefObject objects are accessed directly within the boundaries of the local application domain. The first time an application in a remote application domain accesses a MarshalByRefObject, a proxy is passed to the remote application. Subsequent calls on the proxy are marshaled back to the object residing in the local application domain.
Types must inherit from MarshalByRefObject when the type is used across application domain boundaries, and the state of the object must not be copied because the members of the object are not usable outside the application domain where they were created.
This section contains two code examples. The first code example shows how to create an instance of a class in another application domain. The second code example shows a simple class that can be used for remoting.
Example 1
The following code example shows the simplest way to execute code in another application domain. The example defines a class named Worker that inherits MarshalByRefObject, with a method that displays the name of the application domain in which it is executing. The example creates instances of Worker in the default application domain and in a new application domain.
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The assembly that contains Worker must be loaded into both application domains, but it could load other assemblies that would exist only in the new application domain. |
Example 2
The following example demonstrates a class derived from MarshalByRefObject that is used later in remoting.
System.MarshalByRefObject
IEHost.Execute.IEExecuteRemote
Microsoft.Build.Utilities.AppDomainIsolatedTask
Microsoft.Build.Utilities.TaskItem
Microsoft.Build.Utilities.TaskLoggingHelper
Microsoft.ManagementConsole.Internal.Request
Microsoft.Win32.RegistryKey
System.AddIn.Pipeline.ContractBase
System.AppDomain
System.AppDomainManager
System.ComponentModel.Component
System.ContextBoundObject
System.Data.Common.DataColumnMapping
System.Data.Common.DataColumnMappingCollection
System.Data.Common.DataTableMapping
System.Data.Common.DataTableMappingCollection
System.Data.Common.DbDataReader
System.Data.Common.DbParameter
System.Data.Common.DbParameterCollection
System.Data.Common.DbTransaction
System.Diagnostics.TraceListener
System.DirectoryServices.SearchResultCollection
System.Drawing.Brush
System.Drawing.Drawing2D.CustomLineCap
System.Drawing.Drawing2D.GraphicsContainer
System.Drawing.Drawing2D.GraphicsPath
System.Drawing.Drawing2D.GraphicsPathIterator
System.Drawing.Drawing2D.GraphicsState
System.Drawing.Drawing2D.Matrix
System.Drawing.Font
System.Drawing.FontFamily
System.Drawing.Graphics
System.Drawing.Icon
System.Drawing.Image
System.Drawing.Pen
System.Drawing.Region
System.Drawing.StringFormat
System.EnterpriseServices.Internal.AssemblyLocator
System.EnterpriseServices.RegistrationHelper
System.IO.FileSystemInfo
System.IO.IsolatedStorage.IsolatedStorage
System.IO.Stream
System.IO.TextReader
System.IO.TextWriter
System.Messaging.MessageEnumerator
System.Messaging.MessageQueueEnumerator
System.Net.WebRequest
System.Net.WebResponse
System.Reflection.AssemblyNameProxy
System.Runtime.InteropServices.StandardOleMarshalObject
System.Runtime.Remoting.Lifetime.ClientSponsor
System.Runtime.Remoting.ObjectHandle
System.Speech.Recognition.SrgsGrammar.SrgsElement
System.Threading.RegisteredWaitHandle
System.Threading.Timer
System.Threading.WaitHandle
System.Web.Compilation.ClientBuildManager
System.Web.Compilation.ClientBuildManagerCallback
System.Web.Hosting.ApplicationManager
System.Web.Hosting.HostingEnvironment
System.Web.Hosting.ISAPIRuntime
System.Web.Hosting.VirtualFileBase
System.Web.Hosting.VirtualPathProvider
System.Windows.Forms.BaseCollection
System.Windows.Forms.NativeWindow
System.Windows.Forms.NumericUpDownAccelerationCollection
System.Windows.Forms.OwnerDrawPropertyBag
System.Windows.Forms.TreeNode
System.Windows.Interop.DocObjHost
System.Workflow.Runtime.DebugEngine.DebugController
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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