Check out example codes for "create a file in the directory of the exe and write to it c#". It will help you in understanding the concepts better.

Code Example 1

string GuarnteedWritePath = System.Environment.
                             GetFolderPath(
                                 Environment.SpecialFolder.CommonApplicationData
                             );
            string FilePath = Path.Combine(GuarnteedWritePath, "LogFile.txt");

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