WebException Konstruktorer

public:
 WebException();

public WebException();

Public Sub New ()

Exempel

I följande exempel utlöser en standard 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

Kommentarer

Den parameterlösa konstruktorn initierar en ny instans av WebException klassen. Egenskapen Message initieras till ett systemmeddelande som beskriver felet. Det här meddelandet tar hänsyn till den aktuella systemkulturen. Egenskaperna InnerException och Response initieras till null. Egenskapen Status initieras till RequestCanceled.

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

public WebException(string message);

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

Public Sub New (message As String)

Parametrar

Exempel

I följande exempel genereras ett WebException genom att ett felmeddelande anges.

 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

Kommentarer

Instansen WebException initieras med Message egenskapen inställd på värdet messageför . Om message är nullinitieras egenskapen Message till ett meddelande som tillhandahålls av systemet. Egenskaperna InnerException och Response initieras till null. Egenskapen Status initieras till RequestCanceled.

Se även

• Exception

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

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

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

Parametrar

Kommentarer

Den här konstruktorn implementerar ISerializable gränssnittet för WebException klassen.

Se även

• ISerializable

public:
 WebException(System::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)

Parametrar

Exempel

Följande exempel genererar ett WebException genom att ange ett felmeddelande och en WebExceptionStatus.

 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

Kommentarer

Instansen WebExceptionMessage initieras med egenskapen inställd på värdet message för och Status egenskapen inställd på värdet statusför . Om message är nullinitieras egenskapen Message till ett meddelande som tillhandahålls av systemet. Egenskaperna InnerException och Response initieras till null.

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);

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)

Parametrar

Exempel

I följande exempel genereras ett WebException genom att ett felmeddelande och ett kapslat undantag anges.

   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

Kommentarer

Instansen WebExceptionMessage initieras med egenskapen inställd på värdet message för och InnerException egenskapen inställd på värdet innerExceptionför . Om message är nullinitieras egenskapen Message till ett meddelande som tillhandahålls av systemet. Egenskaperna InnerException och Response initieras till null. Egenskapen Status initieras till RequestCanceled.

Se även

• Exception

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);

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)

Parametrar

Exempel

Följande exempel genererar ett WebException genom att ange ett felmeddelande och en WebExceptionStatus.

      // 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()

Kommentarer

Instansen WebExceptionMessage initieras med egenskapen inställd på värdet messageför , InnerException egenskapen inställd på värdet innerExceptionför , Status egenskapen inställd på värdet statusför och Response egenskapen inställd på värdet responseför . Om message är nullinitieras egenskapen Message till ett meddelande som tillhandahålls av systemet.