Bitwise-or operator used on a sign-extended operand; consider casting to a smaller unsigned type first

The field 'BinaryReader.byteOrder' is never used

The field 'BinaryReader._doubleByteMapBuffer' is assigned but its value is never used

The field 'BinaryReader._floatByteMapBuffer' is assigned but its value is never used

The field 'BinaryWriter._textCharacterWidth' is assigned but its value is never used

The variable 'ex' is declared but never used

The variable 'ex' is declared but never used

The variable 'ex2' is declared but never used

'Encoding.UTF7' is obsolete: 'The UTF-7 encoding is insecure and should not be used. Consider using UTF-8 instead.' (https://aka.ms/dotnet-warnings/SYSLIB0001)