Create the stream with no open file, an open file in read mode, or an open
file with explicit file mode.
mode, if given, is a combination of FileMode.In
(indicating a file that can be read) and FileMode.Out (indicating a file
that can be written).
Opening a file for reading that doesn't exist will error.
Opening a file for writing that doesn't exist will create the file.
The FileMode.OutNew mode will open the file for writing and reset the
length to zero.
The FileMode.Append mode will open the file for writing and move the
file position to the end of the file.
Create the stream with no open file, an open file in read mode, or an open file with explicit file mode. mode, if given, is a combination of FileMode.In (indicating a file that can be read) and FileMode.Out (indicating a file that can be written). Opening a file for reading that doesn't exist will error. Opening a file for writing that doesn't exist will create the file. The FileMode.OutNew mode will open the file for writing and reset the length to zero. The FileMode.Append mode will open the file for writing and move the file position to the end of the file.