String length C#

bytediver_discourse · April 7, 2020, 9:14am

Hi, I have built a XML parser for plcnext in C# and it works fine until a to long string is read from file. Does anyone know the maximum length that the plc (RFC4072s) can handle? Best regards Stefan

Martin_PLCnext_Techn · April 7, 2020, 9:23am

Oooh, an XML parsing library is very interesting. I was only chatting to someone yesterday about this, lamenting the fact that we don’t yet have one of these in PLCnext Engineer. If your library is general-purpose, I would be interested to know more. To answer your question: From PLCnext Engineer help … 2020 04 07 11 19 39 … and: 2020 04 07 11 20 30

user_4223 · April 7, 2020, 11:14am

Thanks Martin! Then I know why the PLC crashed. The string had 128 k characters. The library is kind of generic but I have only implemented the things I need in this project so the functionality is limited. Best regards Stefan.

Martin_PLCnext_Techn · April 7, 2020, 12:27pm

OK, my answer related to strings that are passed as parameters to/from functions & function blocks … not System.String variables in the C# code itself. If that is what you meant, then I don’t know the limit on the size of a System.String object. While Googling the answer to that question, I came across this amusing post, but I don’t think it applies in this case. https://devblogs.microsoft.com/oldnewthing/20070301-00/?p=27803