WebException Konstruktoren

Referenz

Definition

Namespace:: System.Net

Assembly:: System.Net.Requests.dll

Assembly:: System.dll

Assembly:: netstandard.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Initialisiert eine neue Instanz der WebException-Klasse.

Überlädt

WebException()	Initialisiert eine neue Instanz der WebException-Klasse.
WebException(String)	Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung.
WebException(SerializationInfo, StreamingContext)	Veraltet. Initialisiert eine neue Instanz der WebException-Klasse aus der angegebenen SerializationInfo-Instanz und der StreamingContext-Instanz.
WebException(String, WebExceptionStatus)	Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung und dem angegebenen Status.
WebException(String, Exception)	Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung und der angegebenen geschachtelten Ausnahme.
WebException(String, Exception, WebExceptionStatus, WebResponse)	Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung, der geschachtelten Ausnahme, dem Status und der Antwort.

WebException()

Quelle:: WebException.cs

Quelle:: WebException.cs

Quelle:: WebException.cs

Initialisiert eine neue Instanz der WebException-Klasse.

public:
 WebException();

public WebException ();

Public Sub New ()

Beispiele

Im folgenden Beispiel wird ein Standard WebExceptionausgelöst.

try
{
   // A 'Socket' object has been created.
   Socket^ httpSocket = gcnew Socket( AddressFamily::InterNetwork,SocketType::Stream,ProtocolType::Tcp );
   

   // The IPaddress of the unknown uri is resolved using the 'Dns::Resolve' method.

   IPHostEntry^ hostEntry = Dns::Resolve( "http://www.contoso.com" );

   IPAddress^ serverAddress = hostEntry->AddressList[ 0 ];
   IPEndPoint^ endPoint = gcnew IPEndPoint( serverAddress, 80 );
   httpSocket->Connect( endPoint );
   Console::WriteLine( "Connection created successfully" );
   httpSocket->Close();
}
catch ( SocketException^ e ) 
{
   String^ exp = e->Message;
   // Throw the WebException with no parameters.
   throw gcnew WebException;
}


 try   
 {
     // A 'Socket' object has been created.
     Socket httpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

     // The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     
     IPHostEntry hostEntry = Dns.Resolve("http://www.contoso.com");

     IPAddress serverAddress = hostEntry.AddressList[0];
     IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);
     httpSocket.Connect(endPoint);
     Console.WriteLine("Connection created successfully");
     httpSocket.Close();
  }
catch(SocketException e)
  {
  String exp = e.Message;	
  // Throw the WebException with no parameters.
     throw new WebException();
  }

Try
    ' A 'Socket' object has been created.
    Dim httpSocket As New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
    
    ' The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     ' which leads to the 'SocketException' exception. 
    
    Dim hostEntry As IPHostEntry = Dns.Resolve("http://www.contoso.com")
    
    Dim serverAddress As IPAddress = hostEntry.AddressList(0)
    Dim endPoint As New IPEndPoint(serverAddress, 80)
    httpSocket.Connect(endPoint)
    Console.WriteLine("Connection created successfully")
    httpSocket.Close()
Catch e As SocketException
    Dim exp As [String] = e.Message
    ' Throw the WebException with no parameters.
    Throw New WebException()
End Try

Hinweise

Der parameterlose Konstruktor initialisiert eine neue Instanz der WebException -Klasse. Die Message -Eigenschaft wird mit einer vom System bereitgestellten Nachricht initialisiert, die den Fehler beschreibt. Diese Meldung berücksichtigt die aktuelle Systemkultur. Die InnerException Eigenschaften und Response werden mit nullinitialisiert. Die Status-Eigenschaft wird mit RequestCanceled initialisiert.

Gilt für:

WebException(String)

Quelle:: WebException.cs

Quelle:: WebException.cs

Quelle:: WebException.cs

Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung.

public:
 WebException(System::String ^ message);

public WebException (string message);

public WebException (string? message);

new System.Net.WebException : string -> System.Net.WebException

Public Sub New (message As String)

Parameter

message: String

Der Text der Fehlermeldung.

Beispiele

Im folgenden Beispiel wird ein WebException ausgelöst, indem eine Fehlermeldung angegeben wird.

try
{
   // A 'Socket' object has been created.
   Socket^ httpSocket = gcnew Socket( AddressFamily::InterNetwork, SocketType::Stream, ProtocolType::Tcp );
   
   // The IPaddress of the unknown uri is resolved using the 'Dns::Resolve' method.
   IPHostEntry^ hostEntry = Dns::Resolve( connectUri );

   IPAddress^ serverAddress = hostEntry->AddressList[ 0 ];
   IPEndPoint^ endPoint = gcnew IPEndPoint( serverAddress, 80 );
   httpSocket->Connect( endPoint );
   Console::WriteLine( "Connection created successfully" );
   httpSocket->Close();
}
catch ( SocketException^ e ) 
{
   Console::WriteLine( "\nException thrown.\nThe Original Message is: {0}", e->Message );
   
   // Throw the 'WebException' object with a message string specific to the situation.
   throw gcnew WebException( "Unable to locate the Server with 'www.contoso.com' Uri." );
}

 try
{
     // A 'Socket' object has been created.
     Socket httpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

     // The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     IPHostEntry hostEntry = Dns.Resolve(connectUri);

     IPAddress serverAddress = hostEntry.AddressList[0];
     IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);
     httpSocket.Connect(endPoint);
     Console.WriteLine("Connection created successfully");
     httpSocket.Close();
  }
catch(SocketException e)
  {		     
     Console.WriteLine("\nException thrown.\nThe Original Message is: "+e.Message);
     // Throw the 'WebException' object with a message string specific to the situation.
     throw new WebException("Unable to locate the Server with 'www.contoso.com' Uri.");
  }


Try
    ' A 'Socket' object has been created.
    Dim httpSocket As New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
    
    ' The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     
    Dim hostEntry As IPHostEntry = Dns.Resolve(connectUri)
    
    Dim serverAddress As IPAddress = hostEntry.AddressList(0)
    Dim endPoint As New IPEndPoint(serverAddress, 80)
    httpSocket.Connect(endPoint)
    Console.WriteLine("Connection created successfully")
    httpSocket.Close()
Catch e As SocketException
    Console.WriteLine((ControlChars.Cr + "Exception thrown." + ControlChars.Cr + "The Original Message is: " + e.Message))
    ' Throw the 'WebException' object with a message string specific to the situation.
    Throw New WebException("Unable to locate the Server with 'www.contoso.com' Uri.")
End Try

Hinweise

Die WebException -Instanz wird initialisiert, wobei die Message -Eigenschaft auf den Wert von messagefestgelegt ist. Wenn message ist null, wird die Message -Eigenschaft für eine vom System bereitgestellte Nachricht initialisiert. Die InnerException Eigenschaften und Response werden mit nullinitialisiert. Die Status-Eigenschaft wird mit RequestCanceled initialisiert.

Weitere Informationen

Exception

Gilt für:

WebException(SerializationInfo, StreamingContext)

Quelle:: WebException.cs

Quelle:: WebException.cs

Quelle:: WebException.cs

Achtung

This API supports obsolete formatter-based serialization. It should not be called or extended by application code.

Initialisiert eine neue Instanz der WebException-Klasse aus der angegebenen SerializationInfo-Instanz und der StreamingContext-Instanz.

protected:
 WebException(System::Runtime::Serialization::SerializationInfo ^ serializationInfo, System::Runtime::Serialization::StreamingContext streamingContext);

protected WebException (System.Runtime.Serialization.SerializationInfo serializationInfo, System.Runtime.Serialization.StreamingContext streamingContext);

[System.Obsolete("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
protected WebException (System.Runtime.Serialization.SerializationInfo serializationInfo, System.Runtime.Serialization.StreamingContext streamingContext);

new System.Net.WebException : System.Runtime.Serialization.SerializationInfo * System.Runtime.Serialization.StreamingContext -> System.Net.WebException

[<System.Obsolete("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")>]
new System.Net.WebException : System.Runtime.Serialization.SerializationInfo * System.Runtime.Serialization.StreamingContext -> System.Net.WebException

Protected Sub New (serializationInfo As SerializationInfo, streamingContext As StreamingContext)

Parameter

serializationInfo: SerializationInfo

Eine SerializationInfo mit den zum Serialisieren der neuen WebException erforderlichen Informationen.

streamingContext: StreamingContext

Ein StreamingContext mit der Quelle des serialisierten Streams, der der neuen WebException zugeordnet ist.

Attribute: ObsoleteAttribute

Hinweise

Dieser Konstruktor implementiert die ISerializable Schnittstelle für die WebException -Klasse.

Weitere Informationen

ISerializable

Gilt für:

WebException(String, WebExceptionStatus)

Quelle:: WebException.cs

Quelle:: WebException.cs

Quelle:: WebException.cs

Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung und dem angegebenen Status.

public:
 WebException(System::String ^ message, System::Net::WebExceptionStatus status);

public WebException (string message, System.Net.WebExceptionStatus status);

public WebException (string? message, System.Net.WebExceptionStatus status);

new System.Net.WebException : string * System.Net.WebExceptionStatus -> System.Net.WebException

Public Sub New (message As String, status As WebExceptionStatus)

Parameter

message: String

Der Text der Fehlermeldung.

status: WebExceptionStatus

Einer der WebExceptionStatus-Werte.

Beispiele

Im folgenden Beispiel wird ein WebException ausgelöst, indem eine Fehlermeldung und eine WebExceptionStatusangegeben werden.

try
{
   // A 'Socket' object has been created.
   Socket^ httpSocket = gcnew Socket( AddressFamily::InterNetwork, SocketType::Stream, ProtocolType::Tcp );
   
   // The IPaddress of the unknown uri is resolved using the 'Dns::Resolve' method.

   IPHostEntry^ hostEntry = Dns::Resolve( "http://www.contoso.com" );

   IPAddress^ serverAddress = hostEntry->AddressList[ 0 ];
   IPEndPoint^ endPoint = gcnew IPEndPoint( serverAddress, 80 );
   httpSocket->Connect( endPoint );
   Console::WriteLine( "Connection created successfully" );
   httpSocket->Close();
}
catch ( SocketException^ e ) 
{
   Console::WriteLine( "\nException thrown.\nThe Original Message is: {0}", e->Message );
   // Throw the 'WebException' object with a message string and message status specific to the situation.
   throw gcnew WebException( "Unable to locate the Server with 'www.contoso.com' Uri.", WebExceptionStatus::NameResolutionFailure );
}


 try
{
       // A 'Socket' object has been created.
       Socket httpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

      // The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
  
      IPHostEntry hostEntry = Dns.Resolve("http://www.contoso.com");

      IPAddress serverAddress = hostEntry.AddressList[0];
      IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);
      httpSocket.Connect(endPoint);
      Console.WriteLine("Connection created successfully");
      httpSocket.Close();
   }
catch(SocketException e)
  {
      Console.WriteLine("\nException thrown.\nThe Original Message is: "+e.Message);
      // Throw the 'WebException' object with a message string and message status specific to the situation.
      throw new WebException("Unable to locate the Server with 'www.contoso.com' Uri.",WebExceptionStatus.NameResolutionFailure);
  }


Try
    ' A 'Socket' object has been created.
    Dim httpSocket As New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
    
    ' The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     
    Dim hostEntry As IPHostEntry = Dns.Resolve(connectUri)
    
    Dim serverAddress As IPAddress = hostEntry.AddressList(0)
    Dim endPoint As New IPEndPoint(serverAddress, 80)
    httpSocket.Connect(endPoint)
    Console.WriteLine("Connection created successfully")
    httpSocket.Close()
Catch e As SocketException
    Console.WriteLine((ControlChars.Cr + "Exception thrown." + ControlChars.Cr + "The Original Message is: " + e.Message))
    ' Throw the 'WebException' object with a message string and message status specific to the situation.
    Throw New WebException("Unable to locate the Server with 'www.contoso.com' Uri.", WebExceptionStatus.NameResolutionFailure)
End Try

Hinweise

Die WebException -Instanz wird initialisiert, wobei die Message -Eigenschaft auf den Wert von message festgelegt ist und die Status -Eigenschaft auf den Wert von statusfestgelegt ist. Wenn message ist null, wird die Message -Eigenschaft für eine vom System bereitgestellte Nachricht initialisiert. Die InnerException Eigenschaften und Response werden mit nullinitialisiert.

Gilt für:

WebException(String, Exception)

Quelle:: WebException.cs

Quelle:: WebException.cs

Quelle:: WebException.cs

Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung und der angegebenen geschachtelten Ausnahme.

public:
 WebException(System::String ^ message, Exception ^ inner);

public:
 WebException(System::String ^ message, Exception ^ innerException);

public WebException (string message, Exception inner);

public WebException (string? message, Exception? innerException);

public WebException (string message, Exception innerException);

new System.Net.WebException : string * Exception -> System.Net.WebException

new System.Net.WebException : string * Exception -> System.Net.WebException

Public Sub New (message As String, inner As Exception)

Public Sub New (message As String, innerException As Exception)

Parameter

message: String

Der Text der Fehlermeldung.

innerinnerException: Exception

Eine geschachtelte Ausnahme.

Beispiele

Im folgenden Beispiel wird ein WebException ausgelöst, indem eine Fehlermeldung und eine geschachtelte Ausnahme angegeben wird.

try
{
   // A 'Socket' object has been created.
   Socket^ httpSocket = gcnew Socket( AddressFamily::InterNetwork, SocketType::Stream, ProtocolType::Tcp );
   
   // The IPaddress of the unknown uri is resolved using the 'Dns::Resolve' method.

   IPHostEntry^ hostEntry = Dns::Resolve( connectUri );

   IPAddress^ serverAddress = hostEntry->AddressList[ 0 ];
   IPEndPoint^ endPoint = gcnew IPEndPoint( serverAddress, 80 );
   httpSocket->Connect( endPoint );
   Console::WriteLine( "Connection created successfully" );
   httpSocket->Close();
}
catch ( SocketException^ e ) 
{
   Console::WriteLine( "\nException thrown.\nThe Original Message is: {0}", e->Message );
   //  Throw the 'WebException' object with a message string specific to the situation;
   //  and the 'InnerException' that actually led to this exception.
   throw gcnew WebException( "Unable to locate the Server with 'www.contoso.com' Uri.", e );
}


   try
   {
          // A 'Socket' object has been created.
          Socket httpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

          // The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
       
          IPHostEntry hostEntry = Dns.Resolve(connectUri);

          IPAddress serverAddress = hostEntry.AddressList[0];
          IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);
          httpSocket.Connect(endPoint);
          Console.WriteLine("Connection created successfully");
          httpSocket.Close();		 
    }
  catch(SocketException e)
{ 
       Console.WriteLine("\nException thrown.\nThe Original Message is: "+e.Message);
       //  Throw the 'WebException' object with a message string specific to the situation; 
          //  and the 'InnerException' which actually lead to this exception.
          throw new WebException("Unable to locate the Server with 'www.contoso.com' Uri.",e);
    }


Try
    ' A 'Socket' object has been created.
    Dim httpSocket As New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
    
    ' The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     Dim hostEntry As IPHostEntry = Dns.Resolve(connectUri)
    
    Dim serverAddress As IPAddress = hostEntry.AddressList(0)
    Dim endPoint As New IPEndPoint(serverAddress, 80)
    httpSocket.Connect(endPoint)
    Console.WriteLine("Connection created successfully")
    httpSocket.Close()
Catch e As SocketException
    Console.WriteLine((ControlChars.Cr + "Exception thrown." + ControlChars.Cr + "The Original Message is: " + e.Message))
    ' Throw the 'WebException' object with a message string specific to the situation. 
     ' and the 'InnerException' which actually lead to this exception.
    Throw New WebException("Unable to locate the Server with 'www.contoso.com' Uri.", e)
End Try

Hinweise

Die WebException -Instanz wird initialisiert, wobei die Message -Eigenschaft auf den Wert von message festgelegt ist und die InnerException -Eigenschaft auf den Wert von innerExceptionfestgelegt ist. Wenn message ist null, wird die Message -Eigenschaft für eine vom System bereitgestellte Nachricht initialisiert. Die InnerException Eigenschaften und Response werden mit nullinitialisiert. Die Status-Eigenschaft wird mit RequestCanceled initialisiert.

Weitere Informationen

Exception

Gilt für:

WebException(String, Exception, WebExceptionStatus, WebResponse)

Quelle:: WebException.cs

Quelle:: WebException.cs

Quelle:: WebException.cs

Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung, der geschachtelten Ausnahme, dem Status und der Antwort.

public:
 WebException(System::String ^ message, Exception ^ inner, System::Net::WebExceptionStatus status, System::Net::WebResponse ^ response);

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

public WebException (string message, Exception inner, System.Net.WebExceptionStatus status, System.Net.WebResponse response);

public WebException (string? message, Exception? innerException, System.Net.WebExceptionStatus status, System.Net.WebResponse? response);

public WebException (string message, Exception innerException, System.Net.WebExceptionStatus status, System.Net.WebResponse response);

new System.Net.WebException : string * Exception * System.Net.WebExceptionStatus * System.Net.WebResponse -> System.Net.WebException

new System.Net.WebException : string * Exception * System.Net.WebExceptionStatus * System.Net.WebResponse -> System.Net.WebException

Public Sub New (message As String, inner As Exception, status As WebExceptionStatus, response As WebResponse)

Public Sub New (message As String, innerException As Exception, status As WebExceptionStatus, response As WebResponse)

Parameter

message: String

Der Text der Fehlermeldung.

innerinnerException: Exception

Eine geschachtelte Ausnahme.

status: WebExceptionStatus

Einer der WebExceptionStatus-Werte.

response: WebResponse

Eine WebResponse-Instanz, die die Antwort des Remotehosts enthält.

Beispiele

Im folgenden Beispiel wird ein WebException ausgelöst, indem eine Fehlermeldung und eine WebExceptionStatusangegeben werden.

// 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();

      // Send the data. 
      Encoding ASCII = Encoding.ASCII;
      string requestPage = "GET /nhjj.htm HTTP/1.1\r\nHost: " + connectUri + "\r\nConnection: Close\r\n\r\n";
      Byte[] byteGet = ASCII.GetBytes(requestPage);
      Byte[] recvBytes = new Byte[256];

      // Create an 'IPEndPoint' object.
 
      IPHostEntry hostEntry = Dns.Resolve(connectUri);
      IPAddress serverAddress = hostEntry.AddressList[0];
      IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);

      // Create a 'Socket' object  for sending data.
      Socket connectSocket = new 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, 0);
 
      // Receive the information sent by the server.
      Int32 bytesReceived = connectSocket.Receive(recvBytes, recvBytes.Length, 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, 0);
         MemoryStream memoryStream = new MemoryStream(recvBytes);
         getStream = (Stream) memoryStream;
 
         // Create a 'WebResponse' object
         WebResponse myWebResponse = (WebResponse) new HttpConnect(getStream);
         Exception myException = new Exception("File Not found");

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

     connectSocket.Close();


     ' Send the data. 
       Dim ASCII As Encoding = Encoding.ASCII
       Dim requestPage As String = "GET /nhjj.htm HTTP/1.1" + ControlChars.Lf + ControlChars.Cr + "Host: " + connectUri + ControlChars.Lf + ControlChars.Cr + "Connection: Close" + ControlChars.Lf + ControlChars.Cr + ControlChars.Lf + ControlChars.Cr
       Dim byteGet As [Byte]() = ASCII.GetBytes(requestPage)
       Dim recvBytes(256) As [Byte]
       
       ' Create an 'IPEndPoint' object.
       Dim hostEntry As IPHostEntry = Dns.Resolve(connectUri)
       Dim serverAddress As IPAddress = hostEntry.AddressList(0)
       Dim endPoint As New IPEndPoint(serverAddress, 80)
       
       ' Create a 'Socket' object  for sending data.
       Dim connectSocket As New 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, 0)
       
       ' Receive the information sent by the server.
       Dim bytesReceived As Int32 = connectSocket.Receive(recvBytes, recvBytes.Length, 0)
       Dim headerString As [String] = ASCII.GetString(recvBytes, 0, bytesReceived)
      
       ' Check whether 'status 404' is there or not in the information sent by server.
       If headerString.IndexOf("404") <> False Then
           bytesReceived = connectSocket.Receive(recvBytes, recvBytes.Length, 0)
           Dim memoryStream As New MemoryStream(recvBytes)
           getStream = CType(memoryStream, Stream)
           
           ' Create a 'WebResponse' object.
           Dim myWebResponse As WebResponse = CType(New HttpConnect(getStream), WebResponse)
           Dim myException As New Exception("File Not found")
           
           ' Throw the 'WebException' object with a message string, message status,InnerException and WebResponse.
           Throw New WebException("The Requested page is not found.", myException, WebExceptionStatus.ProtocolError, myWebResponse)
       End If 

       connectSocket.Close()

Hinweise

Die WebException -Instanz wird initialisiert, wobei die Message -Eigenschaft auf den Wert von messagefestgelegt ist, die InnerException -Eigenschaft auf den Wert von innerExceptionfestgelegt ist, die Status -Eigenschaft auf den Wert von statusfestgelegt ist und die Response -Eigenschaft auf den Wert von responsefestgelegt ist. Wenn message ist null, wird die Message -Eigenschaft für eine vom System bereitgestellte Nachricht initialisiert.

Gilt für:

Freigeben über

WebException Konstruktoren

Definition

Überlädt

WebException()

Beispiele

Hinweise

Gilt für:

WebException(String)

Parameter

Beispiele

Hinweise

Weitere Informationen

Gilt für:

WebException(SerializationInfo, StreamingContext)

Parameter

Hinweise

Weitere Informationen

Gilt für:

WebException(String, WebExceptionStatus)

Parameter

Beispiele

Hinweise

Gilt für:

WebException(String, Exception)

Parameter

Beispiele

Hinweise

Weitere Informationen

Gilt für:

WebException(String, Exception, WebExceptionStatus, WebResponse)

Parameter

Beispiele

Hinweise

Gilt für:

Zusätzliche Ressourcen