WebClient.OpenRead Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Opens a readable stream for the data downloaded from a resource with the specified URI.
Overloads
OpenRead(String) |
Opens a readable stream for the data downloaded from a resource with the URI specified as a String. |
OpenRead(Uri) |
Opens a readable stream for the data downloaded from a resource with the URI specified as a Uri. |
OpenRead(String)
- Source:
- WebClient.cs
- Source:
- WebClient.cs
- Source:
- WebClient.cs
Opens a readable stream for the data downloaded from a resource with the URI specified as a String.
public:
System::IO::Stream ^ OpenRead(System::String ^ address);
public System.IO.Stream OpenRead (string address);
member this.OpenRead : string -> System.IO.Stream
Public Function OpenRead (address As String) As Stream
Parameters
Returns
A Stream used to read data from a resource.
Exceptions
The address
parameter is null
.
The URI formed by combining BaseAddress, address
is invalid.
-or-
An error occurred while downloading data.
Examples
The following code example opens the resource identified by uriString
and displays the results on the system console. The Stream returned by OpenRead is closed when the data has been read.
// Create a new WebClient instance.
WebClient^ myWebClient = gcnew WebClient;
// Download home page data.
Console::WriteLine( "Accessing {0} ...", uriString );
// Open a stream to point to the data stream coming from the Web resource.
Stream^ myStream = myWebClient->OpenRead( uriString );
Console::WriteLine( "\nDisplaying Data :\n" );
StreamReader^ sr = gcnew StreamReader( myStream );
Console::WriteLine( sr->ReadToEnd() );
// Close the stream.
myStream->Close();
// Create a new WebClient instance.
WebClient myWebClient = new WebClient();
// Download home page data.
Console.WriteLine("Accessing {0} ...", uriString);
// Open a stream to point to the data stream coming from the Web resource.
Stream myStream = myWebClient.OpenRead(uriString);
Console.WriteLine("\nDisplaying Data :\n");
StreamReader sr = new StreamReader(myStream);
Console.WriteLine(sr.ReadToEnd());
// Close the stream.
myStream.Close();
' Create a new WebClient instance.
Dim myWebClient As New WebClient()
' Download home page data.
Console.WriteLine("Accessing {0} ...", uriString)
' Open a stream to point to the data stream coming from the Web resource.
Dim myStream As Stream = myWebClient.OpenRead(uriString)
Console.WriteLine(ControlChars.Cr + "Displaying Data :" + ControlChars.Cr)
Dim sr As New StreamReader(myStream)
Console.WriteLine(sr.ReadToEnd())
' Close the stream.
myStream.Close()
Remarks
Caution
WebRequest
, HttpWebRequest
, ServicePoint
, and WebClient
are obsolete, and you shouldn't use them for new development. Use HttpClient instead.
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 null
, 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.
Note
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 in .NET Framework.
Applies to
OpenRead(Uri)
- Source:
- WebClient.cs
- Source:
- WebClient.cs
- Source:
- WebClient.cs
Opens a readable stream for the data downloaded from a resource with the URI specified as a Uri.
public:
System::IO::Stream ^ OpenRead(Uri ^ address);
public System.IO.Stream OpenRead (Uri address);
member this.OpenRead : Uri -> System.IO.Stream
Public Function OpenRead (address As Uri) As Stream
Parameters
Returns
A Stream used to read data from a resource.
Exceptions
The address
parameter is null
.
The URI formed by combining BaseAddress, address
is invalid.
-or-
An error occurred while downloading data.
Remarks
Caution
WebRequest
, HttpWebRequest
, ServicePoint
, and WebClient
are obsolete, and you shouldn't use them for new development. Use HttpClient instead.
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 null
, 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.
Note
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 in .NET Framework.