WebRequest Class

Article
01/16/2013

[This documentation is for preview only, and is subject to change in later releases. Blank topics are included as placeholders.]

Makes a request to a Uniform Resource Identifier (URI). This is an abstract class.

Inheritance Hierarchy

System. . :: . .Object
  System. . :: . .MarshalByRefObject
    System.Net..::..WebRequest
      System.Net. . :: . .FtpWebRequest
      System.Net. . :: . .HttpWebRequest

Namespace: System.Net
Assembly: System.Http (in System.Http.dll)

Syntax

'Declaration
Public MustInherit Class WebRequest _
    Inherits MarshalByRefObject _
    Implements IDisposable

public abstract class WebRequest : MarshalByRefObject, 
    IDisposable

public ref class WebRequest abstract : public MarshalByRefObject, 
    IDisposable

[<AbstractClass>]
type WebRequest =  
    class
        inherit MarshalByRefObject
        interface IDisposable
    end

public abstract class WebRequest extends MarshalByRefObject implements IDisposable

The WebRequest type exposes the following members.

Constructors

	Name	Description
	WebRequest	Initializes a new instance of the WebRequest class.

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Properties

	Name	Description
	ConnectionGroupName	When overridden in a descendant class, gets or sets the name of the connection group for the request.
	ContentLength	When overridden in a descendant class, gets or sets the content length of the request data being sent.
	ContentType	When overridden in a descendant class, gets or sets the content type of the request data being sent.
	DefaultWebProxy	Gets or sets the global HTTP proxy.
	Headers	When overridden in a descendant class, gets or sets the collection of header name/value pairs associated with the request.
	Method	When overridden in a descendant class, gets or sets the protocol method to use in this request.
	Proxy	When overridden in a descendant class, gets or sets the network proxy to use to access this Internet resource.
	RequestUri	When overridden in a descendant class, gets the URI of the Internet resource associated with the request.
	Timeout	Gets or sets the length of time, in milliseconds, before the request times out.

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Methods

	Name	Description
	Create(String)	Initializes a new WebRequest instance for the specified URI scheme.
	Create(Uri)	Initializes a new WebRequest instance for the specified URI scheme.
	Dispose() () () ()	Releases the resources used by the HttpWebRequest.
	Dispose(Boolean)	Releases the unmanaged resources used by the HttpWebRequest and optionally releases the managed resources.
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Performs clean up operations. (Overrides Object. . :: . .Finalize() () () ().)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetRequestStream	When overridden in a descendant class, returns a Stream for writing data to the Internet resource.
	GetResponse	When overridden in a descendant class, returns a response to an Internet request.
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	RegisterPrefix	Registers a WebRequest descendant for the specified URI.
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Remarks

WebRequest is the abstract base class for the .NET Micro Framework's request/response model for accessing data from the Internet. An application that uses the request/response model can request data from the Internet in a protocol-agnostic manner, in which the application works with instances of the WebRequest class while protocol-specific descendant classes carry out the details of the request.

Requests are sent from an application to a particular URI, such as a Web page on a server. The URI determines the proper descendant class to create from a list of WebRequest descendants registered for the application. WebRequest descendants are typically registered to handle a specific protocol, such as HTTP or FTP, but can be registered to handle a request to a specific server or path on a server.

The WebRequest class throws a WebException when errors occur while accessing an Internet resource. The Status property is one of the WebExceptionStatus values that indicates the source of the error. When Status is WebExceptionStatus..::..ProtocolError, the Response property contains the WebResponse received from the Internet resource.

Because the WebRequest class is an abstract class, the actual behavior of WebRequest instances at run time is determined by the descendant class returned by Create method. For more information about default values and exceptions, see the documentation for the descendant classes, such as HttpWebRequest and FileWebRequest.

Note

Use the Create method to initialize new WebRequest instances. Do not use the WebRequest constructor.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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