Direct Streaming Method CopyTo does not find the end - vb.net

Question

I am reading a SSE by using this method
Public Shared Sub ReadStreamForever(ByVal stream As Stream)
Dim encoder = New UTF8Encoding()
Dim buffer = New Byte(2047) {}
Dim counter As Integer = 0
While True
If stream.CanRead Then
Dim len As Integer = stream.Read(buffer, 0, 2048)
counter = counter + 1
If len > 0 Then
Dim text = encoder.GetString(buffer, 0, len)
SSEApplication.Push(text) 'Here I collect the text slices to a List(of string) object
Else
Exit While
End If
Else
Exit While
End If
End While
SSEApplication.writer() 'Here I write the content to a .txt file
End Sub
With my example data it takes about 2 seconds. I would prefer not to read the stream into memory though and tried this method
Public Shared Sub ReadStreamForever1(ByVal stream As Stream)
Dim output As FileStream = File.OpenWrite("C:\Users\mini_dataset.txt")
While True
If stream.CanRead Then
stream.CopyTo(output)
Else
Exit While
End If
End While
End Sub
But the process ends up in an endless loop (I guess) at least to me it looks like the end of the stream can not be found. I can break the process after a few seconds and all the data are in the .txt file. Any idea what I can do to get the direct stream to file method working?

Answer 1

Stream.CanRead tells you whether a stream supports reading. Since it's apparently readable, While True will go on forever.
Let's verify whether the output Stream.CanWrite instead.
Public Shared Sub ReadStreamForever1(ByVal stream As Stream)
Using output As FileStream = File.OpenWrite("[Output file path]")
If output.CanWrite Then
stream.CopyTo(output)
End If
End Using
End Sub
If the process takes some time and you need to report its progress, you could read the stream using a buffer (I didn't add any error checking but of course a try/catch block should be used):
(Here, with 100 parts division commonly used by a ProgressBar)
Public Sub ReadStreamForever1(ByVal stream As Stream)
Dim BufferLength As Integer = 81920 'As the default stream buffer
Dim Buffer(BufferLength) As Byte
Dim BytesRead As Long = 0L
Using output As FileStream = File.OpenWrite("[Output file path]")
If output.CanWrite Then
Dim Part As Long = stream.Length \ 100
Dim PartCount As Integer = 0
Dim read As Integer = 0
Do
read = stream.Read(Buffer, 0, BufferLength)
If read = 0 Then Exit Do
If (BytesRead / Part > PartCount) Then
PartCount += 1
'ReportWriteProgress(PartCount)
End If
output.Write(Buffer, 0, read)
BytesRead += read
Loop
End If
End Using
End Sub