This code snippet tries to help you to read n bytes from the Serial Port in .NET Framework.
Working with the serial port in .NET, I found what appears to be a fairly common problem:
The above code doesn't return the bytes requested, instead, return the bytes available in buffer and you need to call this function repeatedly in order to obtain the required bytes.
Based in this post I make my own solution with a Extension Method:
Public Function Read(ByVal port As SerialPort, ByVal count As Integer) As Byte()
Dim buffer(count - 1) As Byte
Dim readBytes As Integer
Dim totalReadBytes As Integer
Dim offset As Integer
Dim remaining As Integer = count
readBytes = port.Read(buffer, offset, remaining)
offset += readBytes
remaining -= readBytes
totalReadBytes += readBytes
Loop While remaining > 0 AndAlso readBytes > 0
Catch ex As TimeoutException
ReDim Preserve buffer(totalReadBytes - 1)
The above function loops until all bytes requested are read. If a
TimeOutException occurs (because there are no more data in buffer), the fuction returns the bytes read until the exception occured or a empty byte array if no byte was read.
I hope this can help or if any of you have a better option let us know.
Write your comments, thanks.