WebException Konstruktor

Definisi

Ruang nama:

System.Net

Rakitan:

System.Net.Requests.dll

Menginisialisasi instans baru kelas WebException.

Overload

WebException()	Menginisialisasi instans baru kelas WebException.
WebException(String)	Menginisialisasi instans WebException baru kelas dengan pesan kesalahan yang ditentukan.
WebException(SerializationInfo, StreamingContext)	Kedaluwarsa. Menginisialisasi instans WebException baru kelas dari instans dan StreamingContext yang ditentukanSerializationInfo.
WebException(String, WebExceptionStatus)	Menginisialisasi instans WebException baru kelas dengan pesan kesalahan dan status yang ditentukan.
WebException(String, Exception)	Menginisialisasi instans WebException baru kelas dengan pesan kesalahan yang ditentukan dan pengecualian berlapis.
WebException(String, Exception, WebExceptionStatus, WebResponse)	Menginisialisasi instans WebException baru kelas dengan pesan kesalahan yang ditentukan, pengecualian berlapis, status, dan respons.

WebException()

Sumber:

WebException.cs

Menginisialisasi instans baru kelas WebException.

public:
 WebException();

public WebException ();

Public Sub New ()

Contoh

Contoh berikut menampilkan default WebException.

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

Keterangan

Konstruktor tanpa parameter menginisialisasi instans baru kelas WebException . Properti Message diinisialisasi ke pesan yang disediakan sistem yang menjelaskan kesalahan. Pesan ini memperhitungkan budaya sistem saat ini. Properti InnerException dan Response diinisialisasi ke null. Properti Status diinisialisasi ke RequestCanceled.

WebException(String)

Sumber:

WebException.cs

Menginisialisasi instans WebException baru kelas dengan pesan kesalahan yang ditentukan.

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

public WebException (string? message);

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

Public Sub New (message As String)

Parameter

message

String

Teks pesan kesalahan.

Contoh

Contoh berikut melempar WebException dengan menentukan pesan kesalahan.

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

Keterangan

WebException Instans diinisialisasi dengan properti yang Message diatur ke nilai message. Jika message adalah null, properti diinisialisasi Message ke pesan yang disediakan sistem. Properti InnerException dan Response diinisialisasi ke null. Properti Status diinisialisasi ke RequestCanceled.

Lihat juga

• Exception

WebException(SerializationInfo, StreamingContext)

Sumber:

WebException.cs

Perhatian

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

Menginisialisasi instans WebException baru kelas dari instans dan StreamingContext yang ditentukanSerializationInfo.

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);

[<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

SerializationInfo yang berisi informasi yang diperlukan untuk membuat serialisasi baruWebException.

streamingContext

StreamingContext

StreamingContext yang berisi sumber aliran berseri yang terkait dengan yang baruWebException.

Atribut

ObsoleteAttribute

Keterangan

Konstruktor ini mengimplementasikan ISerializable antarmuka untuk WebException kelas .

Lihat juga

• ISerializable

WebException(String, WebExceptionStatus)

Sumber:

WebException.cs

Menginisialisasi instans WebException baru kelas dengan pesan kesalahan dan status yang ditentukan.

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)

Parameter

message

String

Teks pesan kesalahan.

status

WebExceptionStatus

Salah WebExceptionStatus satu nilai.

Contoh

Contoh berikut melempar WebException dengan menentukan pesan kesalahan dan WebExceptionStatus.

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

Keterangan

WebException Instans diinisialisasi dengan properti yang Message diatur ke nilai message dan Status properti diatur ke nilai status. Jika message adalah null, properti diinisialisasi Message ke pesan yang disediakan sistem. Properti InnerException dan Response diinisialisasi ke null.

WebException(String, Exception)

Sumber:

WebException.cs

Menginisialisasi instans WebException baru kelas dengan pesan kesalahan yang ditentukan dan pengecualian berlapis.

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

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

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

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

Parameter

message

String

Teks pesan kesalahan.

innerException

Exception

Pengecualian berlapis.

Contoh

Contoh berikut melempar WebException dengan menentukan pesan kesalahan dan pengecualian berlapis.

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

Keterangan

WebException Instans diinisialisasi dengan properti yang Message diatur ke nilai message dan InnerException properti diatur ke nilai innerException. Jika message adalah null, properti diinisialisasi Message ke pesan yang disediakan sistem. Properti InnerException dan Response diinisialisasi ke null. Properti Status diinisialisasi ke RequestCanceled.

Lihat juga

• Exception

WebException(String, Exception, WebExceptionStatus, WebResponse)

Sumber:

WebException.cs

Menginisialisasi instans WebException baru kelas dengan pesan kesalahan yang ditentukan, pengecualian berlapis, status, dan respons.

public:
 WebException(System::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

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

Parameter

message

String

Teks pesan kesalahan.

innerException

Exception

Pengecualian berlapis.

status

WebExceptionStatus

Salah WebExceptionStatus satu nilai.

response

WebResponse

WebResponse Instans yang berisi respons dari host jarak jauh.

Contoh

Contoh berikut melempar WebException dengan menentukan pesan kesalahan dan 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();

      // 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()

Keterangan

WebException Instans diinisialisasi dengan Message properti yang diatur ke nilai message, InnerException properti diatur ke nilai innerException, Status properti yang diatur ke nilai status, dan Response properti diatur ke nilai response. Jika message adalah null, properti diinisialisasi Message ke pesan yang disediakan sistem.