Designing a language interpreter & compiler for a simple language

[gasfusion]

Hey guys.
I'm currently taking a course where everyone in the class will code a compiler for a simple C-like language. I'm doing mine in C# and have some general questions for efficiency and the actual architecture.
I've coded a lexer which reads code and categorizes everything into groups.
I'm using a hash table to store all of the lexems, where the key to the table is the order of appearance of a lexem in the code and the value is the type of the lexem which is simply a struct of different predefined tokens (string, integer, sub operator and etc)
In the lexer i'm using a switch while reading the file and determining what i read. Would it be possible to achieve the same with regular expressions?

Also, i'm not quiet sure about this, but this is what i plan on doing with the parser. Since my lexer returns a hash table collection of the entire coded. I can then do all of my error checking here. I will get the value of the first key of the table and then get the second one and performs syntax checks?

I've also read a bit about parse-tree but don't seem to understand what they'd be used for in my case. Is the parse tree going to be used during the actual compilation of a code? I'm not really going to be compiling it, but rather converting it to a compilable C++ code.

If you guys think of something that might improve the architecture of the whole process, please let me know!
Thanks in advance.

[pbmods]

Heya, gasfusion.

I'm going to go ahead and move this thread to the .NET forum, where our resident Experts will be better able to help you out.

[JosAH]

There's a little article series on compilers in the Java Articles section; maybe you
can read it for some ideas of your own.

kind regards,

Jos