The -vcproj option causes Microsoft Visual Studio project and workspace files to be generated that can be used to build the generated code. The files are compatible with Visual Studio version 6.0; but higher versions of Visula Studio can convert these files to the newer formats. This option can be used with the -dll option that will generate project files to compile all generated code into a DLL and -mt that will add multi-threaded compilation options to generated projects.

Because there are several different versions of Visual Studio, the -vcproj option takes an optional argument: the release year of the version of Visual Studio used. This modifies the resulting project to link against the appropriate set of libraries distributed with ASN1C. If no year is specified, the project will link against the usual c and cpp directories. If 2003 is specified, the project will us the c_vs2003 and cpp_vs2003 directories. If 2005 is specified, c_vs2005 and cpp_vs2005 will be used. Likewise, if 2008 is specified, c_vs2008 and cpp_vs2008 will be used.