How to pass string between c++ and c# with null characters inside?

Question

In C++ I have some strings, for example string str = "a\0b\0c";

And I need to pass this string to C# without losing data after "\0",and from c# pass to C++ also without losing data.

Can you help me?

Well.. is this `std::string`, or `System.String^`, or something else? In any case if it's C++/CLI see [this](https://msdn.microsoft.com/en-us/library/bb384865.aspx). — Lucas Trzesniewski, Jan 30 '15 at 11:57
You'll have to pass the length somehow from C# and let C++ construct the `std::string`. — Theodoros Chatzigiannakis, Jan 30 '15 at 12:05
Hmm, is this a COM interop scenario where you should be using [`BSTR`](http://stackoverflow.com/questions/1300122/marshalling-bstrs-from-c-to-c-sharp-with-com-interop) at the C++ end? — Richard Ev, Jan 30 '15 at 12:46
If this is `std::string` and you're in fact using C++/CLI (please make *sure* whether it's the case), then it's as simple as `marshal_as(str)`. Both `std::string` and `System.String` support null characters in the string out of the box. — Lucas Trzesniewski, Jan 30 '15 at 12:49
Just out of curiosity, Can you even have a valid string that safely embeds null characters inside it in C++? — Icemanind, Feb 02 '15 at 18:16
Yes,std::string safely embeds null characters inside it in C++. — Pavlo Denys, Feb 06 '15 at 09:22

score 0 · Accepted Answer · answered Feb 02 '15 at 15:42

Ok, I found answer for my question.Maybe, it`s not very good solution, but it fix my problem. C++:

string EncodeConfigString(string OptionsString)
{
string tempOptions = " ";
if (OptionsString.size() != 0)
{
    vector<int> arrayOfIntCodes;

    for (int i = 0; i < OptionsString.size(); i++)
    {
        int codeOfChar = OptionsString[i];
        tempOptions += std::to_string(codeOfChar) + "&";
    }
}

return tempOptions;
}

C#:

  private string DecodeConfig(StringBuilder OptionsBuilder)
    {
        string result = String.Empty;
        string Options = OptionsBuilder.ToString();

        if (!string.IsNullOrEmpty(Options) && Options.Contains(Consts.AMPERSAND))
        {
            string[] entries = Options.Split(Consts.AMPERSAND);

            StringBuilder chars = new StringBuilder(Consts.OUTPUT_MAX_SIZE);

            for (int i = 0; i < entries.Length; i++)
            {
                int resultParse;

                if (int.TryParse(entries[i], out resultParse))
                {
                    chars.Append((char)resultParse);
                }
            }

            result = chars.ToString();
        }

        return result;

    }

How to pass string between c++ and c# with null characters inside?

1 Answers1