WebException Constructor (String^, Exception^, WebExceptionStatus, WebResponse^)

 

Initializes a new instance of the WebException class with the specified error message, nested exception, status, and response.

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

public:
WebException(
	String^ message,
	Exception^ innerException,
	WebExceptionStatus status,
	WebResponse^ response
)

Parameters

message
Type: System::String^

The text of the error message.

innerException
Type: System::Exception^

A nested exception.

status
Type: System.Net::WebExceptionStatus

One of the WebExceptionStatus values.

response
Type: System.Net::WebResponse^

A WebResponse instance that contains the response from the remote host.

The WebException instance is initialized with the Message property set to the value of message, the InnerException property set to the value of innerException, the Status property set to the value of status, and the Response property set to the value of response. If message is null, the Message property is initialized to a system-supplied message.

The following example throws a WebException by specifying an error message and a WebExceptionStatus.

// Send the data.
Encoding^ ASCII = Encoding::ASCII;
String^ requestPage = String::Concat( "GET /nhjj.htm HTTP/1.1\r\nHost: ", connectUri, "\r\nConnection: Close\r\n\r\n" );
array<Byte>^ byteGet = ASCII->GetBytes( requestPage );
array<Byte>^ recvBytes = gcnew array<Byte>(256);

// Create an 'IPEndPoint' object.

IPHostEntry^ hostEntry = Dns::Resolve( connectUri );
IPAddress^ serverAddress = hostEntry->AddressList[ 0 ];
IPEndPoint^ endPoint = gcnew IPEndPoint( serverAddress,80 );

// Create a 'Socket' object  for sending data.
Socket^ connectSocket = gcnew Socket( AddressFamily::InterNetwork, SocketType::Stream, ProtocolType::Tcp );

// Connect to host using 'IPEndPoint' object.

connectSocket->Connect( endPoint );

// Sent the 'requestPage' text to the host.
connectSocket->Send( byteGet, byteGet->Length, (SocketFlags)(0) );

// Receive the information sent by the server.
Int32 bytesReceived = connectSocket->Receive( recvBytes, recvBytes->Length, (SocketFlags)(0) );
String^ headerString = ASCII->GetString( recvBytes, 0, bytesReceived );

// Check whether 'status 404' is there or not in the information sent by server.
if ( headerString->IndexOf( "404" ) != -1 )
{
   bytesReceived = connectSocket->Receive( recvBytes, recvBytes->Length, (SocketFlags)(0) );
   MemoryStream^ memoryStream = gcnew MemoryStream( recvBytes );
   getStream = (System::IO::Stream^)(memoryStream);

   // Create a 'WebResponse' object
   WebResponse^ myWebResponse = (WebResponse^)(gcnew HttpConnect( getStream ));
   Exception^ myException = gcnew Exception( "File Not found" );

   // Throw the 'WebException' object with a message string, message status, InnerException and WebResponse
   throw gcnew WebException( "The Requested page is not found.",myException,WebExceptionStatus::ProtocolError,myWebResponse );
}

connectSocket->Close();

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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