System.Web Namespace

For .NET Core and .NET 5+, this namespace contains the HttpUtility class.

For .NET Framework, this namespace contains classes and interfaces that enable browser-server communication. These classes include 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 in .NET Framework.

Classes

AspNetHostingPermission

Controls access permissions in ASP.NET hosted environments. This class cannot be inherited.

AspNetHostingPermissionAttribute

Allows security actions for AspNetHostingPermission to be applied to code using declarative security. This class cannot be inherited.

DefaultHttpHandler

Represents the properties and methods of a default HTTP handler.

EventHandlerTaskAsyncHelper

Converts task-returning asynchronous methods into methods that use the asynchronous programming model used in previous versions of ASP.NET and that is based on begin and end events.

HtmlString

Represents an HTML-encoded string that should not be encoded again.

HttpApplication

Defines the methods, properties, and events that are common to all application objects in an ASP.NET application. This class is the base class for applications that are 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.

HttpApplicationStateBase

Serves as the base class for classes that enable information to be shared across multiple sessions and requests within an ASP.NET application.

HttpApplicationStateWrapper

Encapsulates the HTTP intrinsic object that enables information to be shared across multiple requests and sessions within an ASP.NET application.

HttpBrowserCapabilities

Enables the server to gather information on the capabilities of the browser that is running on the client.

HttpBrowserCapabilitiesBase

Serves as the base class for classes that enable the server to gather information about the capabilities of the browser that made the current request.

HttpBrowserCapabilitiesWrapper

Encapsulates the HTTP intrinsic object that enables the server to gather information about the capabilities of the browser that has made the current request.

HttpCachePolicy

Contains methods for setting cache-specific HTTP headers and for controlling the ASP.NET page output cache.

HttpCachePolicyBase

Serves as the base class for classes that contain methods for setting cache-specific HTTP headers and for controlling the ASP.NET page output cache.

HttpCachePolicyWrapper

Encapsulates the HTTP intrinsic object that contains methods for setting cache-specific HTTP headers and for controlling the ASP.NET page output cache.

HttpCacheVaryByContentEncodings

Provides a type-safe way to set the VaryByContentEncodings property of the HttpCachePolicy class.

HttpCacheVaryByHeaders

Provides a type-safe way to set the VaryByHeaders property.

HttpCacheVaryByParams

Provides a type-safe way to set the VaryByParams property.

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.

HttpContextBase

Serves as the base class for classes that contain HTTP-specific information about an individual HTTP request.

HttpContextWrapper

Encapsulates the HTTP intrinsic object that contains 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

Describes an exception that occurred during the processing of HTTP requests.

HttpFileCollection

Provides access to and organizes files uploaded by a client.

HttpFileCollectionBase

Serves as the base class for classes that provide access to files that were uploaded by a client.

HttpFileCollectionWrapper

Encapsulates the HTTP intrinsic object that provides access to files that were uploaded by a client.

HttpModuleCollection

Provides a way to index and retrieve a collection of IHttpModule objects.

HttpParseException

The exception that is thrown when a parse error occurs.

HttpPostedFile

Provides access to individual files that have been uploaded by a client.

HttpPostedFileBase

Serves as the base class for classes that provide access to individual files that have been uploaded by a client.

HttpPostedFileWrapper

Encapsulates the HTTP intrinsic object that provides access to 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.

HttpRequestBase

Serves as the base class for classes that enable ASP.NET to read the HTTP values sent by a client during a Web request.

HttpRequestValidationException

The exception that is thrown when a potentially malicious input string is received from the client as part of the request data. This class cannot be inherited.

HttpRequestWrapper

Encapsulates the HTTP intrinsic object that enables ASP.NET to read the HTTP values that are sent by a client during a Web request.

HttpResponse

Encapsulates HTTP-response information from an ASP.NET operation.

HttpResponseBase

Represents the base class for classes that provides HTTP-response information from an ASP.NET operation.

HttpResponseWrapper

Encapsulates the HTTP intrinsic object that provides 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.

HttpServerUtilityBase

Serves as the base class for classes that provide helper methods for processing Web requests.

HttpServerUtilityWrapper

Encapsulates the HTTP intrinsic object that provides helper methods for processing Web requests.

HttpSessionStateBase

Serves as the base class for classes that provides access to session-state values, session-level settings, and lifetime management methods.

HttpSessionStateWrapper

Encapsulates the HTTP intrinsic object that provides access to session-state values, session-level settings, and lifetime management methods.

HttpStaticObjectsCollection

Provides a collection of application-scoped objects for the StaticObjects property.

HttpStaticObjectsCollectionBase

Serves as the base class for classes that provide a collection of application-scoped objects for the StaticObjects property.

HttpStaticObjectsCollectionWrapper

Encapsulates the HTTP intrinsic object that provides a collection of application-scoped objects for the StaticObjects property.

HttpTaskAsyncHandler

Provides methods that a derived task handler class can implement in order to process an asynchronous task.

HttpUnhandledException

The exception that is thrown when a generic exception occurs.

HttpUtility

Provides methods for encoding and decoding URLs when processing Web requests. This class cannot be inherited.

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.

IisTraceListener

Provides a listener that routes all tracing and debugging output to the IIS 7.0 infrastructure.

MimeMapping

Maps document extensions to content MIME types.

ParserError

Represents a parser error or warning. This class cannot be inherited.

ParserErrorCollection

Manages a set of parser errors detected during parsing. This class cannot be inherited.

PreApplicationStartMethodAttribute

Provides expanded support for application startup.

ProcessInfo

Provides information on processes currently executing.

ProcessModelInfo

Contains methods that return information about worker processes.

SiteMap

The SiteMap class is an in-memory representation of the navigation structure for a site, which is provided by one or more site map providers. This class cannot be inherited.

SiteMapNode

Represents a node in the hierarchical site map structure such as that described by the SiteMap class and classes that implement the abstract SiteMapProvider class.

SiteMapNodeCollection

Provides a strongly typed collection for SiteMapNode objects and implements the IHierarchicalEnumerable interface to support navigating through the collection.

SiteMapProvider

Provides a common base class for all site map data providers, and a way for developers to implement custom site map data providers that can be used with the ASP.NET site map infrastructure as persistent stores for SiteMap objects.

SiteMapProviderCollection

Used by the SiteMap class to track the set of SiteMapProvider objects that are available to the SiteMap during site map initialization. This class cannot be inherited.

SiteMapResolveEventArgs

Provides data for an event that is raised by calling the CurrentNode property of the SiteMapProvider class.

StaticSiteMapProvider

Serves as a partial implementation of the abstract SiteMapProvider class and serves as a base class for the XmlSiteMapProvider class, which is the default site map provider in ASP.NET.

TraceContext

Captures and presents execution details about a Web request. This class cannot be inherited.

TraceContextEventArgs

Provides a collection of trace records to any method that handles the TraceFinished event. This class cannot be inherited.

TraceContextRecord

Represents an ASP.NET trace message and any associated data.

UnvalidatedRequestValues

Provides access to HTTP request values without triggering ASP.NET request validation.

UnvalidatedRequestValuesBase

Serves as the base class for classes that provide access to HTTP request values without triggering ASP.NET request validation.

UnvalidatedRequestValuesWrapper

Provides a wrapper class for the UnvalidatedRequestValuesBase class, and provides access to HTTP request values without triggering ASP.NET request validation.

VirtualPathUtility

Provides utility methods for common virtual path operations.

WebPageTraceListener

Provides a listener that directs Trace messages to ASP.NET Web page outputs.

XmlSiteMapProvider

The XmlSiteMapProvider class is derived from the SiteMapProvider class and is the default site map provider for ASP.NET. The XmlSiteMapProvider class generates site map trees from XML files with the file name extension .sitemap.

Interfaces

IHtmlString

Represents an HTML-encoded string that should not be encoded again.

IHttpAsyncHandler

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 implementing class.

IPartitionResolver

Defines methods that must be implemented for custom session-state partition resolution.

ISubscriptionToken

Represents an interface that is implemented by an object and that can be used to unsubscribe listeners.

ITlsTokenBindingInfo

Provides information about transport layer security (TLS) token binding.

Enums

ApplicationShutdownReason

Specifies why the AppDomain class shut down.

AspNetHostingPermissionLevel

Specifies the trust level that is granted to an ASP.NET Web application.

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.

HttpCookieMode

Specifies how cookies are used for a Web application.

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.

ReadEntityBodyMode

Specifies constants that indicate how the entity body of an HTTP request has been read.

RequestNotification

Indicates when events and other life-cycle events occur while a HttpApplication request is being processed.

RequestNotificationStatus

Specifies the state of a notification in the request pipeline.

SameSiteMode

Specifies constants that indicate the value for the SameSite attribute of the cookie.

TraceMode

Specifies in what order trace messages are emitted into the HTML output of a page.

Delegates

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.

HttpCacheValidateHandler

Represents a method that is called to validate a cached item before the item is served from the cache.

HttpResponseSubstitutionCallback

Represents the method that handles post-cache substitution.

HttpWorkerRequest.EndOfSendNotification

Represents the method that Notifies callers when sending of the response is complete.

SiteMapResolveEventHandler

Represents the method that will handle the SiteMapResolve event of a specific instance of the SiteMapProvider or static SiteMap class.

TaskEventHandler

Represents the asynchronous task that is being processed by an instance of the EventHandlerTaskAsyncHelper class.

TraceContextEventHandler

Represents the method that handles the TraceFinished event of a TraceContext object.