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System.Web Namespace

The System.Web namespace supplies classes and interfaces that enable browser-server communication. This namespace includes the HttpRequest class which provides extensive information about the current HTTP request, the HttpResponse class which manages HTTP output to the client, and the HttpServerUtility class 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.

Namespace hierarchy


Class Description
AspNetHostingPermission Controls access permissions in ASP.NET hosted environments.
AspNetHostingPermissionAttribute Allows security actions for AspNetHostingPermission to be applied to code using declarative security. This class cannot be inherited.
HttpApplication Defines the methods, properties, and events common to all application objects within an ASP.NET application. This class is the base class for applications defined by the user in the global.asax file.
HttpApplicationState Enables sharing of global information across multiple sessions and requests within an ASP.NET application.
HttpBrowserCapabilities Enables the server to gather information on the capabilities of the browser that is running on the client.
HttpCachePolicy Contains methods for setting cache-specific HTTP headers and for controlling the ASP.NET page output cache.
HttpCacheVaryByHeaders Provides a type-safe way to set the VaryByHeaders property that identifies the request headers that ASP.NET adds to the Vary HTTP header sent to the client.
HttpCacheVaryByParams Provides a type-safe way to set the VaryByParams property that identifies the HTTP Get or Post parameters that ASP.NET uses to choose a response from multiple cached responses.
HttpClientCertificate Provides the client certificate fields issued by the client in response to the server's request for the client's identity.
HttpCompileException The exception that is thrown when a compiler error occurs.
HttpContext Encapsulates all HTTP-specific information about an individual HTTP request.
HttpCookie Provides a type-safe way to create and manipulate individual HTTP cookies.
HttpCookieCollection Provides a type-safe way to manipulate HTTP cookies.
HttpException Provides a means of generating HTTP exceptions.
HttpFileCollection Provides access to and organizes files uploaded by a client.
HttpModuleCollection Provides a means of indexing and retrieving a collection of IHttpModule objects.
HttpParseException The exception that is thrown when a parse error occurs.
HttpPostedFile Provides a way to access individual files that have been uploaded by a client.
HttpRequest Enables ASP.NET to read the HTTP values sent by a client during a Web request.
HttpRequestValidationException The exception that is thrown when a potentially dangerous input string is received from the client.
HttpResponse Encapsulates HTTP response information from an ASP.NET operation .
HttpRuntime Provides a set of ASP.NET run-time services for the current application.
HttpServerUtility Provides helper methods for processing Web requests.
HttpStaticObjectsCollection Provides a static objects collection for the StaticObjects property.
HttpUtility Provides methods for encoding and decoding URLs when processing Web requests.
HttpWorkerRequest This abstract class defines the base worker methods and enumerations used by ASP.NET managed code to process requests.
HttpWriter Provides a TextWriter object that is accessed through the intrinsic HttpResponse object.
ProcessInfo Provides information on processes currently executing.
ProcessModelInfo Contains methods that return information about worker processes.
TraceContext Captures and presents execution details about a Web request. This class cannot be inherited.


Interface Description
IHttpAsyncHandler When implemented by a class, defines the contract that HTTP asynchronous handler objects must implement.
IHttpHandler Defines the contract that ASP.NET implements to synchronously process HTTP Web requests using custom HTTP handlers.
IHttpHandlerFactory Defines the contract that class factories must implement to create new IHttpHandler objects.
IHttpModule Provides module initialization and disposal events to the inheriting class.


Delegate Description
BeginEventHandler Represents the method that handles asynchronous events such as application events. This delegate is called at the start of an asynchronous operation.
EndEventHandler Represents the method that handles asynchronous events such as application events. This delegate is called by the event source when completion of the asynchronous operation is signaled by a callback to the BeginEventHandler delegate.
HttpCacheValidateHandler Delegate method that is called when a cached item is validated. Cache items invalidated within the method are treated as cache misses.
Represents the method that notifies callers when sending of the response is complete.


Enumeration Description
HttpCacheability Provides enumerated values that are used to set the Cache-Control HTTP header.
HttpCacheRevalidation Provides enumerated values that are used to set revalidation-specific Cache-Control HTTP headers.
HttpValidationStatus Provides enumerated values that indicate cache validation status.
ProcessShutdownReason Provides enumerated values that indicate why a process has shut down.
ProcessStatus Provides enumerated values that indicate the current status of a process.
TraceMode Specifies in what order trace messages are emitted into the HTML output of a page.

See Also

.NET Framework Class Library