I want to use a single method from a big Class library-dll in C#.
Are there any drawbacks of performance or anything else?
Should I “read” the method code with reflection tool and copy-paste it to my project?
Update: The hard disk space isn’t an issue. My application is web app.
The only one that is actually important is the size of your distributable, if it matters to you. (Users downloading a 30 MB file instead of a 2 MB one). Performance differences will be negligible. Assembly binding and verifying the Strong Name (if it’s signed) hash may take longer, but unlikely to be noticeable to a user.
Probably not; most licensing terms prohibit reverse engineering and/or only partial distribution. Check the license, if any, to see if you can even do it first.