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WebClient.OpenRead Method (Uri)

Opens a readable stream for the data downloaded from a resource with the URI specified as a Uri

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

Public Function OpenRead ( _
	address As Uri _
) As Stream
Dim instance As WebClient
Dim address As Uri
Dim returnValue As Stream

returnValue = instance.OpenRead(address)
public Stream OpenRead (
	Uri address
public function OpenRead (
	address : Uri
) : Stream
Not applicable.



The URI specified as a Uri from which to download data.

Return Value

A Stream used to read data from a resource.

Exception typeCondition


The URI formed by combining BaseAddress, address is invalid.


An error occurred while downloading data.

The OpenRead method creates a Stream instance used to read the contents of the resource specified by the address parameter. This method blocks while opening the stream. To continue executing while waiting for the stream, use one of the OpenReadAsync methods.

If the BaseAddress property is not an empty string ("") and address does not contain an absolute URI, address must be a relative URI that is combined with BaseAddress to form the absolute URI of the requested data. If the QueryString property is not a null reference (Nothing in Visual Basic), it is appended to address.

This method uses the RETR command to download an FTP resource. For an HTTP resource, the GET method is used.


You must call Stream.Close when finished with the Stream to avoid running out of system resources.

Note   This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing.

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0