- Separate into Connect and EstablishConnection step.
- Remove redundant null checks for returned data.
- Only assing PLC stream object once we fully established a connection, and Close otherwise.
- Replace sync implementation with Async call.
The limit calculations did not match what the send and parsing code expected.
sending request header seems to be 19 byte in general.
Also adjust XML comments somewhat, since max PDU really differs a lot between PLC types, from 240 to 960 afaik.
I don't know what the correct expected connection response size is, so I just added checks for the minimal index access by the current code.
This change will just change NullReferenceExceptions into WrongNumberOfBytesException when the PLC response with not enough data for a connection attempt.
Both Synchronous and Asynchronous need to build the same binary data package to write a bytes array. Move that package building out into a common function.
Also use IEnumerable to pass in data instead of converting it to array and back multiple times. Not that happy with the whole ByteArray class, we could probably just use a MemoryStream instead.
This requires reference types that can be null to be annotated by a ? operator, similar to value types.
This gives the advantage that the compiler can warn against any null dereference exceptions, of which this commits elimits a few.
To make the underlying protocol implementation not any more complicated and to eliminate existing problems, and not that precise error reporting, I replaced some return null statements with explicit Exceptions. This lead to the assumption that those core protocoll functions always return non-null objects if they do not throw, making the PLC code simpler.
Adjust some NotConnected tests to look for explicit PlcException instead of NullReferenceException.
* Refactor PLCAddress
- Change fields into properties
- Apply PascalCase naming to all properties
- Make Parse public static with out parameters
* Support creating DataItem from string
* Rename PlcAddress.Address to StartByte
Revert back to using Stream/TcpClient. High performance stuff is moved
to highperformancesockets branch. I think this is interesting, but i also
feel that this is premature optimization. I doubth that this will be a
performance bottleneck ofr the forseeable future.
This reverts commit 1b34716a30.
Note: This keeps the old methods to be backward compatible.
Note: Unforntunatly a lot of whitespace fixes, refactoring and other trivial stuff is
included. It was to hard to split of in a seperate commit.
Note: Async methods does not use exactly the same structure/signature as the
existing methods. "Out" parameters like ReadClass and ReadStruct instead
returns the struct in tuple. Async methods also rely on exceptions
instead of ErrorCodes to communicate exception states to calling client.
* Use TcpClient and use Async methods (ReadAsync/WriteAsync)
* Implemnt async methods for all existing methods
* Implemnt existing methods using tcpclient.
* Split Plc.cs in more files. (Common, Async, Sync, Helpers)
* Mark old methods as Obsolete
* Split tests in two files
* Implement Async tests
