Fix Typescript Errors

I am facing more than 1000 typescript error while compiling. They are mostly the same type of errors, for example, "TS2322: Type 'this' is not assignable to type 'Scanner'." I suspect it is due to a version mismatch of typescript and VS. Need someone to troubleshoot and solve the compiling error. With these errors, the program can still run successfully, however, it cannot run in production mode.