The variable 'ex' is declared but never used

'Assembly.CodeBase' is obsolete: 'Assembly.CodeBase and Assembly.EscapedCodeBase are only included for .NET Framework compatibility. Use Assembly.Location.' (https://aka.ms/dotnet-warnings/SYSLIB0012)

'Exception.Exception(SerializationInfo, StreamingContext)' is obsolete: 'This API supports obsolete formatter-based serialization. It should not be called or extended by application code.' (https://aka.ms/dotnet-warnings/SYSLIB0051)

'S2CFriendRemoveFriendRes.Result' hides inherited member 'ServerResponse.Result'. Use the new keyword if hiding was intended.

'S2CFriendRegisterFavoriteFriendRes.Result' hides inherited member 'ServerResponse.Result'. Use the new keyword if hiding was intended.

'S2CFriendCancelFriendApplicationRes.Result' hides inherited member 'ServerResponse.Result'. Use the new keyword if hiding was intended.

Type parameter 'T' has the same name as the type parameter from outer type 'EntitySerializer<T>'

Type parameter 'T' has the same name as the type parameter from outer type 'EntitySerializer<T>'

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.