Between the 70s and the 90s, almost all programmers used to develop the business logic in COBOL, assure the data persistence in DB2 and rely on CICS to process transactions. Therefore looking to migrate legacy COBOL is a dead end, you don’t have a set of COBOL programs, you have a complex set made of Cobol, CICS and DB2.
So much worse to worry about...
Don’t be fooled, as we stated you don’t only deal with COBOL. In reality, you have so much worse to worry about. What you need is a set of tools that can handle at COBOL compile time
CICS and DB2 statements.
... and we're here to help
You are at the right place, download here a free COBOL compiler that handle CICS messages and SQL DB2 statements at compile time, so that you can recompile your existing code without any precompiler, without changing a line, and retarget DB2 to MS SQL.
Now you have everything you’ll need to modernize your legacy with C#.