Asp. Net each namespace and role

(Quoted from HUNGERW's blog)

Namespace description

Microsoft.csharp supports C # language compilation and generation of code

System includes the underlying class for defining type/array/string/Event/Event Handlers/exception handling/interface/data type conversion/math/Application environment management, etc.

System.coolections contains a set of classes for managing collections of objects (such as lists/queues/arrays/hash tables/dictionaries, etc.)

System.Data mainly includes classes that make up the ADO architecture

System.Diagnostics provides classes for debugging/tracing and interacting with system processes/Event logs/performance counters

System.Drawing provides access to GDI + basic graphics features (namespaces below System.Drawing, including System.Drawing.Drawing2D and System.Drawing.Text, etc., providing more advanced and more specific GDI + Graphics Features) class

System.IO contains types and classes for reading and writing data streams/files and general input/output (I/O) functions

System.Reflection includes classes and interfaces that provide type detection and dynamic binding object functionality

System.reflection.Emit Generating Dynamic assemblies

System.Text object with features for character encoding/converting word converts sequential blocks to bytes fast/convert byte block to character converts sequential blocks

System.Text.RegularExpressions includes providing access. NET Framework regular expression engine classes

System.timer provides a Timer component

System.Web contains classes for implementing browser/server communication and other WEB-related functions

System.Web.Services contains classes for creating and consuming Web services

System.Web.UI contains classes and interfaces for creating user interfaces for Web pages and controls

System.Windows.Forms contains classes for creating a Windows-based user interface

System.Xml provides classes that support XML processing

Microsoft.csharp

Contains classes that support compilation and code generation in the C # language.

Microsoft.JScript

Contains classes that support compilation and code generation in JScript languages.

Microsoft.VisualBasic

Contains classes that support compilation and code generation with Visual Basic. NET language.

Microsoft.Vsa

Contains interfaces that enable you to integrate scripts from the. NET Framework script engine into your application and compile and execute code at run time.

Microsoft.Win32

Provides two types of classes: Classes that handle events raised by the operating system and classes that operate on the system registry.

System

Contains the underlying classes and base classes used to define common values and reference data types, events and event handlers, interfaces, properties, and handling exceptions.

Other classes provide services that support the following operations: Data type conversions, method parameter manipulation, mathematical calculations, remote and local program invocation, application environment management, and governance of managed and unmanaged applications.

System.CodeDom

Contains classes that can be used to represent the elements and structures of a source code document. These elements can be used to establish the structure of the source code document. By using the functionality provided by the System.CodeDom.Compiler namespace, you can export source code documents to source code written in a supported language.

System.CodeDom.Compiler

Contains types for managing the generation and compilation of source code in a supported programming language. Each code generator generates source code in a specific programming language, based on the structure of the Code Document Object Model (CodeDOM) source code model, which consists of elements provided by the System.CodeDom namespace.

System.Collections

Contains interfaces and classes that define collections of various objects, such as lists, queues, bit arrays, hash tables, and dictionaries.

System.Collections.Specialized

Contains a dedicated strongly typed collection, for example, a linked table dictionary, a bit vector, and a collection that contains only strings.

System.ComponentModel

Provides classes for implementing run-time and design-time behavior for components and controls. This namespace includes the base classes and interfaces for the implementation of properties and type converters, data source bindings, and component authorization.

System.ComponentModel.Design

Contains classes that can be used by developers to build custom design-time component behaviors and to configure the component's user interface at design time. The design-time environment provides a system that enables developers to schedule components and configure their properties.

System.ComponentModel.Design.Serialization

Provides support for customizing and controlling the type of serialization at design time.

System.Configuration

Provides classes and interfaces that enable you to programmatically access the errors in the. NET Framework configuration settings and processing configuration files (. config files).

System.Configuration.Assemblies

Contains classes that are used to configure assemblies.

System.Configuration.Install

Provides classes that enable you to write custom installers for your own components. The Installer class is the base class for all custom installers in the. NET Framework.

System.Data

Basically consists of the classes that make up the ADO structure. The ADO structure allows you to build components that can be used to effectively manage data in multiple data sources. In disconnected scenarios such as the Internet, ADO provides a number of tools that can request, update, and reconcile data in a multi-tiered system. The ADO structure can also be implemented in a client application, such as a Windows form, or an HTML page created by ASP.

System.Data.Common

Contains classes that are shared by the. NET Framework Data Provider. The. NET Framework Data provider describes a collection of classes that are used to access a data source, such as a database, in a managed space.

System.Data.Odbc

Encapsulates the ODBC. NET Framework Data Provider. The. NET Framework Data provider describes a collection of classes that are used to access a data source, such as a database, in a managed space. By using the OdbcDataAdapter class, you can populate a dataset that resides in memory and use it to query and update the data source.

For additional information about how to use this namespace, see the OdbcDataReader, OdbcCommand, and OdbcConnection classes.

Note: This namespace is supported only in the. NET Framework version 1.1.

System.Data.OleDb

Encapsulates the OLE DB. NET Framework data Provider. The OLE DB. NET Framework Data Provider describes a collection of classes that are used to access OLE DB data sources in a managed space.

System.Data.OracleClient

Encapsulates the Oracle. NET Framework data Provider. The Oracle. NET Framework Data Provider describes a collection of classes that are used to access an Oracle data source in a managed space.

Note: This namespace is supported only in the. NET Framework version 1.1.

System.Data.SqlClient

encapsulates the SQL Server. NET Framework data Provider. The SQL Server. NET Framework Data Provider describes a collection of classes that are used to access a SQL Server database in a managed space.

System.Data.SqlServerCE

Describes a collection of classes that can be used to access databases in SQL Server CE from a Windows CE-based device in a managed environment. This namespace allows you to create a SQL Server CE database on one device and connect to a SQL Server database on another device or on a remote server.

Note: This namespace is supported only in the. NET Framework version 1.1.

System.Data.SqlTypes

Provides classes that are used for native data types in SQL Server. These classes provide a more secure, faster alternative to other data types. Using the classes in this namespace helps prevent type conversion errors in situations where precision loss can occur. Because other data types and SqlTypes are converted to each other in the background, explicitly creating and using objects within this namespace also produces faster code.

System.Diagnostics

Provides classes that allow interaction with system processes, event logs, and performance counters. This namespace also provides classes that enable you to debug applications and trace code execution. For more information, see Trace and Debug classes.

System.Diagnostics.SymbolStore

Provides classes that enable you to read and write debug symbol information, such as source lines for Microsoft intermediate language (MSIL) mappings. Compilers that target the. NET Framework can store debug symbol information in a programmer's database (PDB) file. Debugger and Code Analyzer tools can read debug symbol information at run time.

System.DirectoryServices

Provides a way to easily access Active Directory from managed code. This namespace consists of two component classes: DirectoryEntry and DirectorySearcher. These two classes use Active Directory service Interface (ADSI) technology. ADSI is a set of interfaces provided by Microsoft and is a flexible tool to handle various network providers. ADSI makes it relatively easy for administrators to find and manage network resources, regardless of the size of the network.

System.Drawing

Provides access to the basic graphics features of GDI +. The System.Drawing.Drawing2D, System.Drawing.Imaging, and System.Drawing.Text namespaces provide more advanced functionality.

System.Drawing.Design

Contains classes that extend the design-time user interface (UI) logic and paint. You can further extend this design-time feature to create the following objects: A custom toolbox item, a type-specific value editor, or a type converter, where a type-specific value editor is used to edit and graphically represent the values of the supported types; type converters are used to convert values between specific types. This namespace provides the basic framework for developing a design-time user interface extension.

System.Drawing.Drawing2D

Provides advanced two and vector graphics capabilities. This namespace includes a gradient brush, a Matrix class (for defining geometric transformations), and a GraphicsPath class.

System.Drawing.Imaging

Provides advanced GDI + image processing capabilities. The basic graphics feature is provided by the System.Drawing namespace.

System.Drawing.Printing

Provides services related to printing. Typically, you can create an instance of the PrintDocument class, set properties that describe the print content, and then call the Print method to actually print the document.

System.Drawing.Text

Provides advanced GDI + layout features. The basic graphics feature is provided by the System.Drawing namespace. The classes in this namespace enable users to create and use a collection of fonts.

System.EnterpriseServices

Provides an important infrastructure for enterprise-class applications. COM + provides a service structure for the component programming model deployed in an enterprise environment. This namespace provides access to COM + services for. NET Framework objects, making. NET Framework objects more suitable for enterprise applications.

System.EnterpriseServices.CompensatingResourceManager

Provides classes that enable you to use Compensating Resource Manager (CRM) in managed code. CRM is a service provided by COM + that enables you to include non-transactional objects in a Microsoft distributed Transaction Coordinator (DTC) transaction. Although CRM does not provide the full resource Manager functionality, they provide transactional atomicity (all or nothing behavior) and persistence through the recovery log.

System.EnterpriseServices.Internal

Provides infrastructure support for COM + services. Classes and interfaces in this namespace are specifically designed to support incoming system.enterpriseservices from unmanaged COM + classes.

System.Globalization

Contains classes that define culture-related information, including language, country/region, calendars in use, format patterns for dates, currency, numbers, and sort order of strings. These classes are useful for writing globalization (internationalization) applications.

System.IO

Contains types that allow synchronous and asynchronous read and write to data streams and files.

System.IO.IsolatedStorage

Contains types that allow the creation and use of isolated stores. By using these stores, you can read and write data that is not accessible to less trusted code, and you can prevent exposing sensitive information that can be saved elsewhere in the file system. The data is stored in the data compartment independent of the current user and the assembly in which the code resides.

System.Management

Provides access to a rich set of management information and management events, which are about systems, devices, and applications that conform to the Windows Management Instrumentation (WMI) infrastructure.

System.Management.Instrumentation

Provides the classes that are required to standardize application management and expose management information and events to potential users through WMI. This allows users such as Microsoft Application Center or Microsoft Operations Manager to easily manage your applications, Administrator scripts or other applications (managed applications and unmanaged applications) can also monitor and configure your application.

System.Messaging

Provides classes that enable you to connect, monitor, and manage message queues on a network and send, receive, or view messages.

System.Net

Provides a simple programming interface for the various protocols used by the current network. The WebRequest and WebResponse classes form the basis of so-called pluggable protocols, which are implementations of a network service that enables you to develop applications that use Internet resources without having to consider the specifics of each protocol.

System.Net.Sockets

Provides a managed implementation of the Windows sockets (Winsock) interface for developers who require strict control over network access.

System.Reflection

Contains classes and interfaces that provide managed views of loaded types, methods, and fields, and has the ability to dynamically create and invoke types.

System.Reflection.Emit

Contains classes that allow the compiler or tool to emit metadata and Microsoft intermediate language (MSIL) and optionally generate a PE file on disk. The primary clients for these classes are the scripting engine and the compiler.

System.Resources

Provides classes and interfaces that allow developers to create, store, and manage various culture-specific resources used in applications.

System.Runtime.CompilerServices

Provides functionality for compiler writers that use managed code to specify properties in metadata that affect the runtime behavior of the common language runtime. The classes in this namespace are used only for compiler writers.

System.Runtime.InteropServices

Provides a variety of members that support COM Interop and platform invoke services. If you are unfamiliar with these services, see interoperate with unmanaged code.

System.Runtime.InteropServices.CustomMarshalers

Supports the. NET infrastructure and is not used directly from your code.

System.Runtime.InteropServices.Expando

Contains the IExpando interface, which allows you to modify an object by adding or removing members of the object.

System.Runtime.Remoting

Provides classes and interfaces that enable developers to create and configure distributed applications.

System.Runtime.Remoting.Activation

Provides classes and objects that support server and client remote object activation.

System.Runtime.Remoting.Channels

Contains classes that support and process channel and channel sinks that are used as transport media when clients invoke methods on remote objects.

System.Runtime.Remoting.Channels.Http

Contains channels that use the HTTP protocol to transfer messages and objects to and from remote locations. By default, the HTTP channel encodes object and method calls in SOAP format for transmission, but other encoding and decoding formatter sinks can also be specified in the configuration properties of a channel.

System.Runtime.Remoting.Channels.Tcp

Contains channels that use the TCP protocol to transfer messages and objects to and from remote locations. By default, the TCP channel encodes object and method calls in binary format for transmission, but other encoding and decoding formatter sinks can also be specified in the configuration properties of a channel.

System.Runtime.Remoting.Contexts

Contains objects that define the context in which all objects reside. A context is an ordered sequence of attributes that defines the environment in which the object is located. Contexts are created during the activation of an object that is configured to require certain automated services such as synchronization, transactions, just-in-time (JIT) activation, security, and so on. Multiple objects can be persisted within a context.

System.Runtime.Remoting.Lifetime

Contains classes that manage the lifetime of remote objects. Traditionally, the Distributed garbage Collection feature uses reference counts and pings to control the lifetime of an object. This mechanism works when there are fewer clients per service, but it does not work when there are thousands of clients per service. The remoting lifetime service associates each service with a lease, and when the lease expires, the service is deleted. The Lifetime Service can act as a traditional distributed garbage collector, and can be well tuned when the number of clients for each service increases.

System.Runtime.Remoting.Messaging

Contains classes that are used to create and remotely process messages. The remoting infrastructure uses messages to communicate with remote objects. Messages are used to transfer remote method calls, to activate remote objects, and to communicate information. A Message object carries a set of named properties, including action identifiers, Representative information, and parameters.

System.Runtime.Remoting.Metadata

Contains classes and properties that you can use to customize the generation and processing of SOAP for objects and fields. Classes in this namespace can be used to indicate soapaction, type output, XML element names, and XML namespace URI methods.

System.Runtime.Remoting.Metadata.W3cXsd2001

Contains XML schema definitions (XSD) defined by the World Wide Web Consortium in 2001. The specification of "XML Schema Part2:data types" (the second part of XML Schemas: data types) in the broad information system determines the format and behavior of various data types. This namespace contains wrapper classes for data types that conform to the specifications. All date and time types conform to the ISO standard specification.

System.Runtime.Remoting.MetadataServices

Contains classes that are used by the Soapsuds.exe command-line tool and user code to convert between XML schemas in the metadata and remoting infrastructure.

System.Runtime.Remoting.Proxies

Contains classes that control and provide proxy functionality. A proxy is a local object that acts as a remote object image. Proxies enable clients to access objects across remoting boundaries.

System.Runtime.Remoting.Services

Contains service classes that provide functionality for the. NET Framework.

System.Runtime.Serialization

Contains classes that can be used to serialize and deserialize objects. Serialization is the process of converting an object or object graph into a linear sequence of bytes to store or transfer to another location. Deserialization is the process of accepting stored information and recreating the object with this information.

System.Runtime.Serialization.Formatters

Provides generic enumerations, interfaces, and classes used by the serialization formatter.

System.Runtime.Serialization.Formatters.Binary

Contains the BinaryFormatter class that can be used to serialize and deserialize objects in binary format.

System.Runtime.Serialization.Formatters.Soap

Contains the SoapFormatter class that can be used to serialize and deserialize objects in SOAP format.

System.Security

Provides the infrastructure for the. NET Framework security system, including the base class for permissions.

System.Security.Cryptography

Provides cryptographic services, including secure encoding and decoding of data, as well as many other operations such as hashing, random number generation, and message authentication.

System.Security.Cryptography.X509Certificates

The common language runtime implementation that contains the Authenticode V.3 certificate. This certificate is signed with a private key that uniquely identifies the holder of the certificate.

System.Security.Cryptography.XML

Contains classes that support the creation and validation of XML digital signatures. The classes in this namespace implement the World Wide Web Consortium recommendation "Xml-signature Syntax and Processing" (XML signature Syntax and processing), as described in Http://www.w3.org/TR/xmldsig-core/.

System.Security.Permissions

Defines classes that control operations and resource access based on policy.

System.Security.Policy

Contains code groups, membership conditions, and evidence. These three types of classes are used to create rules that are applied by the. NET Framework security policy system. The evidence class is the input to the security policy, and the membership condition is the switch; both create a policy statement and determine the set of permissions granted. Policy levels and code groups are the structure of the policy hierarchy. Code groups are the encapsulation of rules and are arranged hierarchically in the policy level.

System.Security.Principal

Defines the principal object that represents the security context in which code is run.

System.ServiceProcess

Provides classes that enable you to implement, install, and control Windows service applications. A service is an executable file that does not require a long-running user interface. The process of implementing a service includes inheriting from the ServiceBase class, defining specific behaviors that are handled when the incoming start, stop, pause, and continue commands are passed, and defining custom behavior and actions taken when the system shuts down.

System.Text

Contains classes that represent ASCII, Unicode, UTF-7, and UTF-8 character encodings, an abstract base class for converting between word converts sequential blocks and byte blocks, and helper classes that do not need to create intermediate instances of strings to manipulate and format string objects.

System.Text.RegularExpressions

Contains classes that provide access to the. NET Framework regular expression engine. This namespace provides regular expression functionality that can be used on any platform or language that is running in the Microsoft. NET Framework.

System.Threading

Provides classes and interfaces that support multithreaded programming. In addition to the classes used to synchronize thread activity and data access (mutexes, Monitor, interlocked, AutoResetEvent, and so on), this namespace also includes a ThreadPool class (which allows you to use the system-provided thread pool) and a Timer Class (The callback method is executed on threads in the thread pool).

System.Timers

Provides a Timer component that allows events to be raised at a specified interval.

System.Web

Provides classes and interfaces that support browser/server communication. This namespace includes the HttpRequest class (which provides a lot of information about the current HTTP request), the HttpResponse class (which manages the HTTP-to-client output), and the HttpServerUtility object (which provides access to server-side utilities and processes). System.Web also includes classes for Cookie manipulation, file transfer, exception information, and output cache control.

System.Web.Caching

Provides classes for caching common data on the server. This includes the Cache class, which is a dictionary where you can store arbitrary data objects, such as hash tables and datasets. It also provides invalidation functionality for these objects and gives you a way to add and remove those objects. You can also add objects that depend on other files or cache entries, and execute callbacks to notify your application when an object is removed from the cache.

System.Web.Configuration

Contains classes for setting up an ASP.

System.Web.Hosting

Provides the ability to host an ASP. NET application from an externally hosted application from Microsoft Internet Information Services (IIS).

System.Web.Mail

Contains classes that enable you to construct and send messages using the CDOSYS message component. Mail messages are sent through the built-in SMTP mail service or any SMTP server in Microsoft Windows 2000. The classes in this namespace can be used from ASP. NET or any managed application.

System.Web.Mobile

Contains the core features required to build an ASP. NET mobile WEB application, including authentication and error handling.

System.Web.Security

Contains classes for implementing ASP. NET security in a WEB server application.

System.Web.Services

Contains classes that enable you to create XML Web services with ASP. NET and XML Web services clients. XML WEB Services are applications that provide the ability to exchange messages in loosely coupled environments that use standard protocols such as HTTP, XML, XSD, SOAP, and WSDL. With XML Web services, you can generate modular applications within and between companies in heterogeneous environments, enabling them to interoperate with a wide variety of implementations, platforms, and devices. The parts of the SOAP-based XML message for these applications can be strictly defined (structured and typed) or loosely defined (using arbitrary XML). These messages can evolve over time and do not break the protocol, which is fundamental to the flexibility and reliability of XML Web services as a future web building block.

System.Web.Services.Configuration

Consists of classes that configure how XML Web services created with ASP.

System.Web.Services.Description

Consists of classes that enable you to publicly describe XML Web services using the Web Service Description Language (WSDL). Each class in this namespace corresponds to a specific element in the WSDL specification, and the class hierarchy corresponds to the XML structure of a valid WSDL document.

System.Web.Services.Discovery

Consists of classes that allow XML Web services clients to locate XML Web services available on a Web server through processes called XML Web services discovery.

System.Web.Services.Protocols

Consists of classes that define the protocol used to transfer data between the XML Web services client and the XML Web services created by ASP over the network during communication.

System.Web.SessionState

Provides classes and interfaces that support storing data on a server that is specific to a single client in a WEB application. Session state data is used to provide the client with the appearance of a persistent connection to the application. State information can be stored in local process memory, or, for a network farm configuration, you can store state information out-of-process using the ASP. NET State Service or SQL Server database.

System.Web.UI

Provides classes and interfaces that enable you to create controls and pages that appear in the Web application as a user interface on a Web page. This namespace includes the control class, which provides a common set of functionality for all controls, whether HTML controls, Web controls, or user controls. It also includes the page control, which is automatically generated whenever a request is made to a page in the Web application. Classes are also available that provide WEB Forms server control data binding capabilities, the ability to save the view state of a given control or page, and the analysis capabilities that are applicable to both programmable and text controls.

System.Web.UI.Design

Contains classes that you can use to extend support for Web forms design time.

System.Web.UI.Design.WebControls

Contains classes that you can use to extend design-time support for Web server controls.

System.Web.UI.HtmlControls

Contains a collection of classes that enable you to create HTML server controls on a Web forms page. The HTML server control runs on the server and maps directly to the standard HTML markup supported by most browsers. This enables you to programmatically control HTML elements on a Web forms page.

System.Web.UI.MobileControls

Contains a set of ASP. NET server controls that can intelligently render your application for different mobile devices.

System.Web.UI.MobileControls.Adapters

Contains the core device adapter classes that are used by the ASP. NET mobile controls to customize devices and support extended devices.

System.Web.UI.WebControls

Contains classes that enable you to create Web server controls on a Web page. The WEB server control runs on the server and includes form controls such as buttons and text boxes. They also include special controls that are similar to calendars. Because WEB server controls are running on the server, these elements can be controlled programmatically. Web server controls are more abstract than HTML server controls. Their object model does not necessarily reflect the HTML syntax.

System.Windows.Forms

Contains classes for creating Windows-based applications that take advantage of the rich user interface features in the Microsoft Windows operating system.

System.Windows.Forms.Design

Contains classes that support design-time configuration and behavior of Windows forms components. These classes include designer classes that provide support for Windows forms components (that is, a set of design-time services), UITypeEditor classes for configuring specific property types, and classes for importing ActiveX controls.

System.Xml

Provides support for standard-based XML processing.

System.Xml.Schema

Contains XML classes that provide support for standards-based XML Schema definition language (XSD) schemas.

System.Xml.Serialization

Contains classes that are used to serialize objects into XML-formatted documents or streams.

System.Xml.XPath

Contains the XPath parser and the compute engine. It supports the 1.0 version of the XML Path Language (XPath) recommendation (Www.w3.org/TR/xpath).

System.Xml.Xsl

Provides Extensible Stylesheet Transformation (XSLT) transformation support. It supports the Www.w3.org/TR/xslt XSL Transformation (XSLT) version 1.0 recommendation.

Asp. Net each namespace and role