EndGetRequestStream Method

FileWebRequest.EndGetRequestStream Method (IAsyncResult)

 

Ends an asynchronous request for a Stream instance that the application uses to write data.

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

Public Overrides Function EndGetRequestStream (
	asyncResult As IAsyncResult
) As Stream

Parameters

asyncResult
Type: System.IAsyncResult

An IAsyncResult that references the pending request for a stream.

Return Value

Type: System.IO.Stream

A Stream object that the application uses to write data.

Exception Condition
ArgumentNullException

asyncResult is null.

The EndGetRequestStream method completes an asynchronous stream request that was started by the BeginGetRequestStream method.

System_CAPS_noteNote

To avoid timing issues with garbage collection, be sure to close the response stream by calling the Close method on the stream returned by the GetResponseStream method after calling the EndGetResponse method.

The following example uses the EndGetRequestStream method to end the asynchronous request for a Stream object.

Public Class RequestDeclare
    Public myFileWebRequest As FileWebRequest
    Public userinput As [String]


    Public Sub New()
        myFileWebRequest = Nothing
    End Sub ' New
End Class ' RequestDeclare


Class FileWebRequest_reqbeginend
    Public Shared allDone As New ManualResetEvent(False)

    ' Entry point which delegates to C-style main Private Function.
    Public Overloads Shared Sub Main()
        Main(System.Environment.GetCommandLineArgs())
    End Sub


    Overloads Shared Sub Main(args() As String)
        If args.Length < 2 Then
            Console.WriteLine(ControlChars.Cr + "Please enter the file name as command line parameter:")
            Console.WriteLine("Usage:FileWebRequest_reqbeginend <systemname>/<sharedfoldername>/<filename>")
	    Console.WriteLine("Example: FileWebRequest_reqbeginend shafeeque/shaf/hello.txt")

        Else
            Try

                ' Place a webrequest.
                Dim myWebRequest As WebRequest = WebRequest.Create(("file://" + args(1)))

                ' Create an instance of the 'RequestDeclare' and associate the 'myWebRequest' to it.		
                Dim requestDeclare As New RequestDeclare()
                requestDeclare.myFileWebRequest = CType(myWebRequest, FileWebRequest)
                ' Set the 'Method' property of 'FileWebRequest' object to 'POST' method.
                requestDeclare.myFileWebRequest.Method = "POST"
                Console.WriteLine("Enter the string you want to write into the file:")
                requestDeclare.userinput = Console.ReadLine()

                ' Begin the Asynchronous request for getting file content using 'BeginGetRequestStream()' method .
                Dim r As IAsyncResult = CType(requestDeclare.myFileWebRequest.BeginGetRequestStream(AddressOf ReadCallback, requestDeclare), IAsyncResult)
                allDone.WaitOne()

                Console.Read()
            Catch e As ProtocolViolationException
                Console.WriteLine(("ProtocolViolationException is :" + e.Message))
            Catch e As InvalidOperationException
                Console.WriteLine(("InvalidOperationException is :" + e.Message))
            Catch e As UriFormatException
                Console.WriteLine(("UriFormatExceptionException is :" + e.Message))
            End Try

        End If 
    End Sub 'Main


    Private Shared Sub ReadCallback(ar As IAsyncResult)
        Try

            ' State of the request is asynchronous.
            Dim requestDeclare As RequestDeclare = CType(ar.AsyncState, RequestDeclare)
            Dim myFileWebRequest As FileWebRequest = requestDeclare.myFileWebRequest
            Dim sendToFile As [String] = requestDeclare.userinput

            ' End the Asynchronus request by calling the 'EndGetRequestStream()' method.
            Dim readStream As Stream = myFileWebRequest.EndGetRequestStream(ar)

            ' Convert the string into byte array.
            Dim encoder As New ASCIIEncoding()
            Dim byteArray As Byte() = encoder.GetBytes(sendToFile)

            ' Write to the stream.
            readStream.Write(byteArray, 0, sendToFile.Length)
            readStream.Close()
            allDone.Set()


            Console.WriteLine(ControlChars.Cr +"The String you entered was successfully written into the file.")
            Console.WriteLine(ControlChars.Cr +"Press Enter to continue.")

            Catch e As ApplicationException
            Console.WriteLine(("ApplicationException is :" + e.Message))
        End Try

    End Sub ' ReadCallback 

.NET Framework
Available since 1.1
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