Beginning C# 2008 Objects: From Concept to Code

3.7. Objects As Fields

When we first discussed the fields and methods associated with the Student class, we stated that some of the fields could be represented by predefined types provided by the C# language, whereas the types of a few others (advisor, courseLoad, and transcript) were left undefined. Let's now put what we learned about user-defined types to good use.

Instead of declaring the Student class's advisor field as simply a string representing the advisor's name, we'll declare it to be a user-defined type—namely, type Professor, another class that we invented (see Table 3-2).

Table 3.2. Student Class Fields, Revisited

Field	Type
name	string
studentId	string
birthdate	DateTime
address	string
major	string
gpa	double
advisor	Professor
courseLoad	???
transcript ...