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Ron Petrusha
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Merge pull request #738 from dotnet/master
Update Live with current Master
2 parents f5cb930 + b2cb36b commit ce192cb

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‎snippets/csharp/VS_Snippets_CLR/eventsoverview/cs/programtruncated.cs‎

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Original file line numberDiff line numberDiff line change
@@ -5,9 +5,9 @@ namespace ConsoleApplication1
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// <snippet2>
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class Program
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{
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static void Main(string[] args)
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static void Main()
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{
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Counter c = new Counter();
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var c = new Counter();
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c.ThresholdReached += c_ThresholdReached;
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// provide remaining implementation for the class
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protected virtual void OnThresholdReached(EventArgs e)
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{
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EventHandler handler = ThresholdReached;
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if (handler != null)
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{
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handler(this, e);
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}
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handler?.Invoke(this, e);
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}
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// provide remaining implementation for the class

‎snippets/visualbasic/VS_Snippets_CLR/eventsoverview/vb/module1truncated.vb‎

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@@ -2,7 +2,7 @@
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Module Module1
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Sub Main()
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Dim c As Counter = New Counter()
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Dim c As New Counter()
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AddHandler c.ThresholdReached, AddressOf c_ThresholdReached
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' provide remaining implementation for the class

‎snippets/visualbasic/VS_Snippets_Remoting/NclSslClientAsync/VB/clientasync.vb‎

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@@ -0,0 +1,227 @@
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Imports System.IO
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Imports System.Security.Cryptography.X509Certificates
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Imports System.Text
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Imports System.Security.Authentication
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Imports System.Net.Sockets
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Imports System.Net.Security
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Imports System.Net
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Imports System.Collections
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Imports System.Threading
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' NclSslClientAsync
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'<snippet0>
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Namespace Examples.Ssl
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' The following example demonstrates the client side of a
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' client-server application that communicates using the
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' SslStream and TcpClient classes.
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' After connecting to the server and authenticating,
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' the client sends the server a message, recieves a message from the server,
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' and then terminates. Messages sent to and from the server are terminated
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' with '<EOF>'.
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Public Class SslTcpClient
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' complete is used to terminate the application when all
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' asynchronous calls have completed or any call has thrown an exception.
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' complete might be used by any of the callback methods.
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Shared complete As Boolean = False
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' e stores any exception thrown by an asynchronous method so that
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' the mail application thread can display the exception and terminate gracefully.
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' e might be used by any of the callback methods.
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Shared e As Exception = Nothing
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' <snippet8>
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' readData and buffer holds the data read from the server.
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' They is used by the ReadCallback method.
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Shared readData As New StringBuilder()
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Shared buffer As Byte() = New Byte(2048) {}
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' </snippet8>
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'<snippet1>
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' The following method is invoked by the CertificateValidationDelegate.
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Public Shared Function ValidateServerCertificate(
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sender As Object,
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certificate As X509Certificate,
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chain As X509Chain,
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sslPolicyErrors As SslPolicyErrors) As Boolean
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Console.WriteLine("Validating the server certificate.")
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If sslPolicyErrors = SslPolicyErrors.None Then Return True
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Console.WriteLine("Certificate error: {0}", sslPolicyErrors)
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' Do not allow this client to communicate with unauthenticated servers.
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Return False
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End Function
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'</snippet1>
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'<snippet2>
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Public Shared Function SelectLocalCertificate(
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sender As Object,
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targetHost As String,
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localCertificates As X509CertificateCollection,
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remoteCertificate As X509Certificate,
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acceptableIssuers As String()) As X509Certificate
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Console.WriteLine("Client is selecting a local certificate.")
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If acceptableIssuers IsNot Nothing AndAlso acceptableIssuers.Length > 0 AndAlso
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localCertificates IsNot Nothing AndAlso localCertificates.Count > 0 Then
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' Use the first certificate that is from an acceptable issuer.
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For Each certificate As X509Certificate In localCertificates
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Dim issuer As String = certificate.Issuer
72+
If Array.IndexOf(acceptableIssuers, issuer) <> -1 Then
73+
Return certificate
74+
End If
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Next
76+
End If
77+
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If localCertificates IsNot Nothing AndAlso localCertificates.Count > 0 Then
79+
Return localCertificates(0)
80+
End If
81+
82+
Return Nothing
83+
End Function
84+
'</snippet2>
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'<snippet3>
86+
Shared Sub AuthenticateCallback(ar As IAsyncResult)
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88+
Dim stream = CType(ar.AsyncState, SslStream)
89+
90+
Try
91+
stream.EndAuthenticateAsClient(ar)
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Console.WriteLine("Authentication succeeded.")
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Console.WriteLine("Cipher: {0} strength {1}", stream.CipherAlgorithm, stream.CipherStrength)
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Console.WriteLine("Hash: {0} strength {1}", stream.HashAlgorithm, stream.HashStrength)
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Console.WriteLine("Key exchange: {0} strength {1}", stream.KeyExchangeAlgorithm, stream.KeyExchangeStrength)
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Console.WriteLine("Protocol: {0}", stream.SslProtocol)
97+
' Encode a test message into a byte array.
98+
' Signal the end of the message using the "<EOF>".
99+
Dim message As Byte() = Encoding.UTF8.GetBytes("Hello from the client.<EOF>")
100+
' Asynchronously send a message to the server.
101+
stream.BeginWrite(message, 0, message.Length, New AsyncCallback(AddressOf WriteCallback), stream)
102+
Catch authenticationException As Exception
103+
e = authenticationException
104+
complete = True
105+
Return
106+
End Try
107+
108+
End Sub
109+
'</snippet3>
110+
'<snippet4>
111+
Shared Sub WriteCallback(ar As IAsyncResult)
112+
Dim stream = CType(ar.AsyncState, SslStream)
113+
Try
114+
Console.WriteLine("Writing data to the server.")
115+
stream.EndWrite(ar)
116+
' Asynchronously read a message from the server.
117+
stream.BeginRead(buffer, 0, buffer.Length, New AsyncCallback(AddressOf ReadCallback), stream)
118+
Catch writeException As Exception
119+
e = writeException
120+
complete = True
121+
Return
122+
End Try
123+
End Sub
124+
'</snippet4>
125+
'<snippet5>
126+
127+
Shared Sub ReadCallback(ar As IAsyncResult)
128+
' Read the message sent by the server.
129+
' The end of the message is signaled using the
130+
' "<EOF>" marker.
131+
Dim stream = CType(ar.AsyncState, SslStream)
132+
Dim byteCount As Integer
133+
Try
134+
Console.WriteLine("Reading data from the server.")
135+
byteCount = stream.EndRead(ar)
136+
' Use Decoder class to convert from bytes to UTF8
137+
' in case a character spans two buffers.
138+
Dim decoder As Decoder = Encoding.UTF8.GetDecoder()
139+
Dim chars = New Char(decoder.GetCharCount(buffer, 0, byteCount)) {}
140+
decoder.GetChars(buffer, 0, byteCount, chars, 0)
141+
readData.Append(chars)
142+
' Check for EOF or an empty message.
143+
If readData.ToString().IndexOf("<EOF>") = -1 AndAlso byteCount <> 0 Then
144+
' We are not finished reading.
145+
' Asynchronously read more message data from the server.
146+
stream.BeginRead(buffer, 0, buffer.Length, New AsyncCallback(AddressOf ReadCallback), stream)
147+
Else
148+
Console.WriteLine("Message from the server: {0}", readData.ToString())
149+
End If
150+
Catch readException As Exception
151+
e = readException
152+
complete = True
153+
Return
154+
End Try
155+
complete = True
156+
End Sub
157+
'</snippet5>
158+
'<snippet7>
159+
Public Shared Function Main(args As String()) As Integer
160+
161+
Dim serverName As String
162+
If args Is Nothing OrElse args.Length < 2 Then
163+
Console.WriteLine("To start the client specify the host name and" +
164+
" one or more client certificate file names.")
165+
Return 1
166+
End If
167+
'<snippet6>
168+
' Server name must match the host name and the name on the host's certificate.
169+
serverName = args(0)
170+
' Create a TCP/IP client socket.
171+
Dim client As New TcpClient(serverName, 80)
172+
Console.WriteLine("Client connected.")
173+
' Create an SSL stream that will close the client's stream.
174+
Dim sslStream As New SslStream(
175+
client.GetStream(), False,
176+
New RemoteCertificateValidationCallback(AddressOf ValidateServerCertificate),
177+
New LocalCertificateSelectionCallback(AddressOf SelectLocalCertificate))
178+
'</snippet6>
179+
' Create the certificate collection to hold the client's certificate.
180+
Dim clientCertificates As New X509CertificateCollection()
181+
Dim i = 1
182+
While i < args.Length
183+
Dim certificate As X509Certificate = X509Certificate.CreateFromCertFile(args(i))
184+
clientCertificates.Add(certificate)
185+
i += 1
186+
End While
187+
188+
' Begin authentication.
189+
' The server name must match the name on the server certificate.
190+
sslStream.BeginAuthenticateAsClient(
191+
serverName, clientCertificates,
192+
SslProtocols.Ssl3, True,
193+
New AsyncCallback(AddressOf AuthenticateCallback), sslStream)
194+
195+
' User can press a key to exit application, or let the
196+
' asynchronous calls continue until they complete.
197+
Console.WriteLine("To quit, press the enter key.")
198+
199+
Do
200+
' Real world applications would do work here
201+
' while waiting for the asynchronous calls to complete.
202+
Thread.Sleep(100)
203+
Loop While complete <> True AndAlso Console.KeyAvailable = False
204+
205+
If Console.KeyAvailable Then
206+
Console.ReadLine()
207+
Console.WriteLine("Quitting.")
208+
client.Close()
209+
sslStream.Close()
210+
Return 1
211+
End If
212+
213+
If e IsNot Nothing Then
214+
Console.WriteLine("An exception was thrown: {0}", e.ToString())
215+
End If
216+
217+
sslStream.Close()
218+
client.Close()
219+
Console.WriteLine("Good bye.")
220+
Return 0
221+
222+
End Function
223+
'</snippet7>
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225+
End Class
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227+
End Namespace

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