Is there any way I can convert a string of code into executable code at runtime in c#?
So if I have a file of predicates
This is normal text in a txt
You can use CSharpCodeProvider class, but you'll need to build quite a bit of extra code around the snippet, as you have to provide a full class. I did this for my "Snippy" tool for C# in Depth, and you can download the source to get one simple example of how it can be done.
However, life is becoming much simpler in this area with Roslyn - you may want to get hold of the CTP and explore that.
Have a look at the Roslyn ScriptEngine.