Actuall This is not the case thought vb is an event driven programm so is c
But the major difference is in their architecure and thus they require different compilers.
But in case you are asking how write and compile c program from vb application
What you can do is write a vb application to create a standard frontend to write c programs and other fuctions that you want ot add and pass the program to a command line c compiler for compilation. In any case you would be requiring a c compiler.