.net 4.0 what is new

NET Framework, or that do not target a specific version of. NET Framework, is unaffected. For more information, see the "Culture and task-based asynchronous operations" section of the CultureInfo class topic.

It can be used to persist data across threads. Value property was explicitly changed, or because the thread encountered a context transition. Three convenience methods, Task.

CompletedTask , Task. FromCanceled , and Task. FromException , have been added to the task-based asynchronous pattern TAP to return completed tasks in a particular state.

You now can use the EventSource class to log administrative or operational messages to the event log, in addition to any existing ETW sessions created on the machine. In the past, you had to use the Microsoft. EventSource NuGet package for this functionality.

This functionality is now built-into. Allows specially attributed classes and arrays as well as primitive types to be passed as a payload. Causes Start and Stop events to tag events between them with an ID that represents all currently active activities.

To support these features, the overloaded Write method has been added to the EventSource class. Changes have been made to layout rounding to reduce instances of clipping in controls with borders. By default, this feature is enabled only if your TargetFrameworkAttribute is set to. Applications that target earlier versions of the framework but are running on. Support for automatically loading the right cursor based on DPI setting has been added to System.

Customer reports on Connect that touch produces unpredictable behavior have been addressed in. WPF in. This allows you to create non-rectangular and transparent child windows in your top-level windows. You can enable this feature by setting the HwndSourceParameters. UsesPerPixelTransparency property to true. It is now possible to select which protocol to use, or to disable old lesser secure protocols.

This can be done either by setting the SslProtocols property or by adding the following to a configuration file. There are two ways to do this:. Users can specify a string that WCF will use as a prefix for the connection group name. Two messages with different prefixes are sent using different underlying HTTP connections. Properties property. Users can also enable a feature that ensures that messages sent using channels created by different channel factories will use different underlying HTTP connections.

To enable this feature, users must set the following appSetting to true :. You can now specify the number of seconds a workflow service will hold on to an out-of-order operation request when there is an outstanding "non-protocol" bookmark before timing out the request. A "non-protocol" bookmark is a bookmark that is not related to outstanding Receive activities. Some activities create non-protocol bookmarks within their implementation, so it may not be obvious that a non-protocol bookmark exists.

These include State and Pick. So if you have a workflow service implemented with a state machine or containing a Pick activity, you will most likely have non-protocol bookmarks.

You specify the interval by adding a line like the following to the appSettings section of your app. The default value is 60 seconds. If value is set to 0, out-of-order requests are immediately rejected with a fault with text that looks like this:.

This is the same message that you receive if an out-of-order operation message is received and there are no non-protocol bookmarks. If the value of the FilterResumeTimeoutInSeconds element is non-zero, there are non-protocol bookmarks, and the timeout interval expires, the operation fails with a timeout message.

You can now include the distributed transaction identifier for the transaction that has caused an exception derived from TransactionException to be thrown. You do this by adding the following key to the appSettings section of your app. Windows 10 includes a new high-scalability networking algorithm that makes better use of machine resources by reusing local ports for outbound TCP connections. NET apps to take advantage of the new behavior. In previous versions of Windows, there was an artificial concurrent connection limit typically 16,, the default size of the dynamic port range , which could limit the scalability of a service by causing port exhaustion when under load.

SocketOptionName enumeration value. The ServicePointManager. ReusePort property. By default, the ServicePointManager. ReusePort property to true. Developers writing a sockets-only application can specify the System. SocketOptionName option when calling a method such as Socket. SetSocketOption so that outbound sockets reuse local ports during binding.

A new property, IdnHost , has been added to the Uri class to better support international domain names and PunyCode. This feature has been expanded in. NET Core primarily supports the Unicode encodings and by default provides limited support for code page encodings. You can add support for code page encodings available in. NET Framework but unsupported in.

NET Core by registering code page encodings with the Encoding. RegisterProvider method. For more information, see System. This technology produces apps that have faster startup and execution times. For more information, see Compiling Apps with.

NET Native. For an overview of. NET Native and Compilation. Your apps are compiled to native code by default when you compile them with Visual Studio or later. For more information, see Getting Started with. To support debugging. Http namespace are now available as open-source packages on GitHub. To access the code, see. NET on GitHub. For more information and how to contribute to these packages, see Introduction to. NET ,. NET apps.

The new HttpResponse. AddOnSendingHeaders methods let you inspect and modify response headers and status code as the response is being flushed to the client app.

The HostingEnvironment. QueueBackgroundWorkItem method lets you schedule small background work items. NET tracks these items and prevents IIS from abruptly terminating the worker process until all background work items have completed. This method can't be called outside an ASP. NET managed app domain. HeadersWritten and HttpResponseBase. HeadersWritten properties return Boolean values that indicate whether the response headers have been written.

StatusCode which throw exceptions if the headers have been written will succeed. Resizing in Windows Forms controls. This feature has been expanded. You can now use the system DPI setting to resize components of the following additional controls for example, the drop-down arrow in combo boxes :.

New workflow feature. PromoteAndEnlistDurable method to request the following:. This can be done within the same app domain, and doesn't require any extra unmanaged code to interact with MSDTC to perform the promotion. The new method can be called only when there's an outstanding call from System. Transactions to the IPromotableSinglePhaseNotification Promote method that's implemented by the promotable enlistment. Profiling improvements. The following new unmanaged profiling APIs provide more robust profiling:.

Previous ICorProfiler implementations supported lazy loading of dependent assemblies. The new profiling APIs require dependent assemblies that are injected by the profiler to be loadable immediately, instead of being loaded after the app is fully initialized.

Debugging improvements. The following new unmanaged debugging APIs provide better integration with a profiler. You can now access metadata inserted by the profiler as well as local variables and code produced by compiler ReJIT requests when dump debugging.

Event tracing changes. This enables Advanced Power Management APM vendors to provide lightweight tools that accurately track the costs of individual requests and activities that cross threads. The method may be used by an enlistment that was previously created by Transaction. Promote method. It asks System. Transactions to promote the transaction to an MSDTC transaction and to "convert" the promotable enlistment to a durable enlistment.

After this method completes successfully, the IPromotableSinglePhaseNotification interface will no longer be referenced by System. Transactions , and any future notifications will arrive on the provided ISinglePhaseNotification interface. The enlistment in question must act as a durable enlistment, supporting transaction logging and recovery. Refer to Transaction. EnlistDurable for details. In addition, the enlistment must support ISinglePhaseNotification. This method can only be called while processing an ITransactionPromoter.

Promote call. If that is not the case, a TransactionException exception is thrown. Visual Studio Update 2 includes updates to the Portable Class Library templates to support these scenarios:.

XAML types in portable libraries when you target Windows 8. You can create a portable Windows Runtime component. For more information about these changes, see Portable Class Library. NET Framework content set now includes documentation for. NET Native, which is a precompilation technology for building and deploying Windows apps. NET Native compiles your apps directly to native code, rather than to intermediate language IL , for better performance.

For details, see Compiling Apps with. You can now browse through the. NET Framework source code online, download the reference for offline viewing, and step through the sources including patches and updates during debugging. For more information, see the blog entry A new look for. NET Reference Source. Automatic binding redirection for assemblies. Starting with Visual Studio , when you compile an app that targets.

You can also enable this feature for projects that target older versions of. Ability to collect diagnostics information to help developers improve the performance of server and cloud applications. Ability to explicitly compact the large object heap LOH during garbage collection. For more information, see the GCSettings. LargeObjectHeapCompactionMode property. Additional performance improvements such as ASP.

NET Framework update. For details, see the. NET app suspend blog post. You can use the system DPI setting to resize components of controls for example, the icons that appear in a property grid by opting in with an entry in the application configuration file app.

This feature is currently supported in the following Windows Forms controls:. Return values in the Visual Studio debugger. When you debug a managed app in Visual Studio , the Autos window displays return types and values for methods.

This information is available for desktop, Windows Store, and Windows Phone apps. For more information, see Examine return values of method calls. Edit and Continue for bit apps. The existing limitations remain in effect for both bit and bit apps see the last section of the Supported Code Changes C article. Async-aware debugging.

To make it easier to debug asynchronous apps in Visual Studio , the call stack hides the infrastructure code provided by compilers to support asynchronous programming, and also chains in logical parent frames so you can follow logical program execution more clearly. A Tasks window replaces the Parallel Tasks window and displays tasks that relate to a particular breakpoint, and also displays any other tasks that are currently active or scheduled in the app.

You can read about this feature in the "Async-aware debugging" section of the. Better exception support for Windows Runtime components. In Windows 8. You can read about this feature in the "Windows Store app development" section of the. For new features in ASP. NET 4. Ability to reduce system restarts by detecting and closing. NET Framework 4 applications during deployment. See Reducing System Restarts During. Support for arrays that are larger than 2 gigabytes GB on bit platforms.

This feature can be enabled in the application configuration file. Better performance through background garbage collection for servers.

When you use server garbage collection in. Background just-in-time JIT compilation, which is optionally available on multi-core processors to improve application performance. See ProfileOptimization. Ability to limit how long the regular expression engine will attempt to resolve a regular expression before it times out. See the Regex. MatchTimeout property. Ability to define the default culture for an application domain.

See the CultureInfo class. Console support for Unicode UTF encoding. See the Console class. Support for versioning of cultural string ordering and comparison data. See the SortVersion class. Better performance when retrieving resources. See Package and deploy resources. Zip compression improvements to reduce the size of a compressed file. See the System.

Compression namespace. Ability to customize a reflection context to override default reflection behavior through the CustomReflectionContext class.

IdnMapping class is used on Windows 8. Delegation of string comparison to the operating system, which implements Unicode 6. NET Framework is used on Windows 8. When running on other platforms, the. NET Framework includes its own string comparison data, which implements Unicode 5. See the String class and the Remarks section of the SortVersion class. Ability to compute the hash codes for strings on a per application domain basis.

Type reflection support split between Type and TypeInfo classes. See Reflection in the. Convention-based programming model that enables you to create parts based on naming conventions rather than attributes. A subset of MEF that you can use when you create Windows 8. This subset is available as a downloadable package from the NuGet Gallery.

Composition package. These features add a task-based model for performing asynchronous operations. NET Framework assembly. For more information, see Resgen. Managed Profile Guided Optimization Mpgo. The command-line tool generates profile data for native image application assemblies. See Mpgo. Starting with Visual Studio , you can use Mpgo.

These include improved performance, increased control, improved support for asynchronous programming, a new dataflow library, and improved support for parallel debugging and performance analysis. See the entry What's New for Parallelism in.

For more information, see the following resources:. For more information, see the new System. Http and System. Headers namespaces. Support is also included for a new programming interface for accepting and interacting with a WebSocket connection by using the existing HttpListener and related classes.

WebSockets namespace and the HttpListener class. For more information, see Uri and related classes. For more information, see the System. Mail namespace. Improved IPv6 support. NetworkInformation namespace.

Dual-mode socket support. For more information, see the Socket and TcpListener classes. The new Ribbon control, which enables you to implement a ribbon user interface that hosts a Quick Access Toolbar, Application Menu, and tabs. New features for the VirtualizingPanel and Dispatcher classes.

Improved performance when displaying large sets of grouped data, and by accessing collections on non-UI threads. Data binding to static properties, data binding to custom types that implement the ICustomTypeProvider interface, and retrieval of data binding information from a binding expression.

Ability to set the amount of time that should elapse between property changes and data source updates. Improved support for implementing weak event patterns. Also, events can now accept markup extensions. Changes in default transport property values to reduce the likelihood that you will have to set them. Updates to the XmlDictionaryReaderQuotas class to reduce the likelihood that you will have to manually configure quotas for XML dictionary readers.

Validation of WCF configuration files by Visual Studio as part of the build process, so you can detect configuration errors before you run your application. Ability to generate metadata in a single WSDL document by appending? Websockets support to enable true bidirectional communication over ports 80 and with performance characteristics similar to the TCP transport. ChannelFactory caching support. Support for a UDP transport that enables developers to write services that use "fire and forget" messaging.

A client sends a message to a service and expects no response from the service. State machine workflows, which were first introduced as part of. This update included several new classes and activities that enabled developers to create state machine workflows. These classes and activities were updated for. Activities for creating state machine workflows, including: StateMachine , State , and Transition.

Ability to automatically create a Sequence activity when a second child activity is added to a container activity, and to include both activities in the Sequence activity. Panning support, which enables the visible portion of a workflow to be changed without using the scroll bars. A new Document Outline view that shows the components of a workflow in a tree-style outline view and lets you select a component in the Document Outline view. Auto-connect and auto-insert for activities and transitions in state machine and flowchart workflows.

Storage of the view state information for a workflow in a single element in the XAML file, so you can easily locate and edit the view state information. Workflow projects that use Visual Basic will use Visual Basic expressions, and C workflow projects will use C expressions.

C workflow projects that were created in Visual Studio and that have Visual Basic expressions are compatible with C workflow projects that use C expressions. Routing Service. Support for WS-Discovery.

Standard Endpoints. Workflow Services. Target Framework Attribute. WorkFlow Workflow Activity Model. Rich Composite Activity Options. Expanded Built-In Activity Library. Explicit Activity Data Model.

Enhanced Hosting, Persistence, and Tracking Options. Next Recommended Reading. Windows 10 Vs Windows Visual Studio Vs Visual Studio Understanding Matplotlib With Examples.

Understanding Numpy With Examples. C Evolution. Everything That Every. Understanding Pandas With Examples. The Finalize method is called automatically by the runtime. CLR has a garbage collector GC , which periodically checks for objects in heap that are no longer referenced by any object or program.

It calls the Finalize method to free the memory used by such objects. The Dispose method is called by the programmer. Dispose is another method to release the memory used by an object. The Dispose method needs to be explicitly called in code to dereference an object from the heap. The Dispose method can be invoked only by the classes that implement the IDisposable interface. Code access security CAS is part of the. NET security model that prevents unauthorized access of resources and operations, and restricts the code to perform particular tasks.

Managed code is the code that is executed directly by the CLR instead of the operating system. Unmanaged code is the code that is executed directly by the operating system outside the CLR environment. It is directly compiled to native machine code which depends on the machine configuration. In the managed code, since the execution of the code is governed by CLR, the runtime provides different services, such as garbage collection, type checking, exception handling, and security support.

These services. In the unmanaged code, the allocation of memory, type safety, and security is required to be taken care of by the developer. If the unmanaged code is not properly handled, it may result in memory leak.

Tuple is a fixed-size collection that can have elements of either same or different data types. Similar to arrays, a user must have to specify the size of a tuple at the time of declaration. Tuples are allowed to hold up from 1 to 8 elements and if there are more than 8 elements, then the 8th element can be defined as another tuple.

Tuples can be specified as parameter or return type of a method. What is garbage collection? Explain the difference between garbage collections in.

Garbage collection prevents memory leaks during execution of programs. Garbage collector is a low-priority process that manages the allocation and deallocation of memory for your application. It checks for the unreferenced variables and objects. If GC finds any object that is no longer used by the application, it frees up the memory from that object. GC has changed a bit with the introduction of. Collect method contains the following overloaded methods:. Another new feature introduced in.

NET is to notify you when the GC. Collect method is invoked and completed successfully by using different methods. This concurrent GC allocates memory while running and uses current segment which is 16 MB on a workstation for that. After that, all threads are suspended. In case of background GC, a separate ephemeral GC — gen0 and gen1 can be started, while the full GC — gen0, 1, and 2 — is already running. There are two key concepts of CAS security policy- code groups and permissions. A code group contains assemblies in it in a manner that each.

NET assembly is related to a particular code group and some permissions are granted to each code group. For example, using the default security policy, a control downloaded from a Web site belongs to the Zone, Internet code group, which adheres to the permissions defined by the named permission set.

Normally, the named permission set represents a very restrictive range of permissions. This entry was posted in ASP. NET Framework 4. Numerics namespace. NET Framework? What is.