DotNet FAQ. Few more to follow
hi,
here are some .Net FAQ. Few more to follow
Please feel free to post ur comments or corrections and add new questions.
1.What is CLR?
The common language runtime is one of the main components of the .NET Framework. It provides the run-time environment and various run-time services to applications. These components load the IL code of an application into the runtime, compile the IL code into native code, execute the code, and enforce security. In addition, these components implement type safety and provide automatic memory management and thread support. The components of the common language runtime also provide an exception manager, a common debugger, and other system services, such as base class library support and interoperability.
2.what are finalizers?
Finalizers are the methods that contain the cleanup code that is executed before the object is garbage collected. The process of executing cleanup code is called finalization. The Dispose and Finalize methods are called finalizers.
3.What is an assembly,GAC?
Assemblies are the fundamental units of application development and deployment. They are the smallest unit for versioning and configuring security. They contain the type metadata, MSIL code, and the assembly manifest.
Assemblies can be private or shared. A private assembly is installed in the installation directory of an application and is accessible to that application only. On the other hand, a shared assembly is shared by multiple applications. A shared assembly has a strong name and is installed in the GAC. A strong name consists of an assembly name, version, culture information, digital signature, and public key information.
The .NET Framework maintains a machine-wide code cache, the GAC, which enables you to store the code shared by multiple applications. You need to assign a strong name to an assembly to place it in the GAC and make it globally accessible.
4.Application configuration
The .NET Framework uses various configuration and security policy files to control the behavior of applications at run time. A configuration file is an XML document that contains predefined elements.
Machine configuration, Machine.config file.
This file is located in the %runtime installation path%\Config directory and contains settings that affect all the applications that run on the machine.
Application configuration file.
This file contains the settings required to configure an individual application. These settings take the precedence over the machine.config file
Security configuration files.
The security configuration files contain security permissions for a hierarchy of code groups. Code groups are logical groups of code that are related to each other through common characteristics such as application directory, strong name, URL, site, and zone.
5. Run-Time Hosts
A host needs to load the runtime into a process before the runtime can execute an application. The .NET Framework provides different run-time hosts for different run-time environments. These include the run-time hosts for ASP.NET applications, shell executables, and downloadable components that run within Internet Explorer. These run-time hosts run in an unmanaged environment.
The run-time host calls the CorBindToRuntimeEx method that is located in the Mscoree.h API to load and initialize the runtime. While calling the CorBindToRuntimeEx method, the run-time host sets the Loader Optimization value, which determines whether the runtime will host domain-neutral assemblies.
6. .Net Framework tools
Assembly Linker al.exe
IL Disassembler ildasm.exe
The .NET Framework Configuration tool, Mscorcfg.msc, is a Microsoft Management Console (MMC) snap-in that enables you to manage and configure assemblies located in the GAC.
----------Windows Service----------
1.What is a Windows Service and how does its lifecycle differ from a "standard" EXE?
Windows services run as background processes. These applications do not have a user interface, which makes them ideal for tasks that do not require any user interaction.Windows service is different from normal exe in installation,debugging, and executing methods.
2.windows service architecture
The Windows service architecture consists of three components:
Service application: An application that consists of one or more services that provide the desired functionality
Service controller application: An application that enables you to control the behavior of a service.
Service Control Manager: A utility that enables you to control the services that are installed on a computer
Classes of the System.ServiceProcess Namespace :
ServiceBase: You override the methods in the ServiceBase class to create a service application. The methods of this class enable you to specify the behavior of your service application. eg.,onStart,onStop etc.,
ServiceProcessInstaller and ServiceInstaller: These classes enable you to define the process of installing and uninstalling your service application.
ServiceController: The methods of this class enable you to manipulate the behavior of your service application. For example, you can use the methods of this class to start and stop the service. You use the methods of this class in the application that you create to manage and control a service. eg.,Start,Stop,Close,Continue etc.,
installutil.exe is used ti install and uninstall the service.
------COM Serviced components-----
1.What are different Component Services of COM ?
Transactions, queued components (QC), security, loosely coupled events (LCE), JIT activation, and object pooling.
2.Transaction?
Transactions group a set of tasks into a single execution unit. Each transaction begins with a specific task and ends when all the tasks in the group successfully complete. If any of the tasks fails, the transaction fails. Therefore, a transaction has only two results: success or failure. Incomplete steps result in the failure of the transaction.
The properties of transaction-supported applications are atomicity, concurrency, isolation, and durability (ACID).
3.what is Queued component?
The Queued Component service of COM is based on the MSMQ model. MSMQ is a middle-tier service that enables the asynchronous delivery of messages to named queues. The MSMQ system arranges the method calls in a queue and executes them automatically when the component is available. Therefore, queued components can be used to execute client methods even after the component is unavailable or offline, ensuring the continuous running of a distributed application.
4.what is JIT Activation?
The JIT activation service ensures that the client application has references to objects as long as it requires them. This ensures that a client application does not use the valuable memory resources of the server to save the object references.
5. What is Object Pooling?
COM provides an automated service for configuring a component so that it can maintain ready-to-use and active object instances in a pool to process client requests. The COM object pooling service is responsible for managing the pool and ensuring the activation and reuse of the pool objects.The object pool adds to the scalability of an application by providing the means for recycling COM objects. Object pooling is, therefore, a resource saver that cuts down the costs of creating new instances of the same object time and again.
6. What is a serviced component?
A serviced component is a class that derives from the System.EnterpriseServices.ServicedComponent class, which is the base class for all classes that use COM component services. You create and register each service component before it can access the COM services.
Author:
P kanthi kumar (2006-9-08:01:15)
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