Thanks. I kind of figured it out right before I saw your reply. It appears that there are several things you can do in C# that would make your program difficult, if not impossible, to follow.

I've been reading the chapter on polymorpism, and they have a lengthy discussion on assigning a derived class reference to a base class reference. I would think this type of programming would make it potentially very difficult to follow the method calls. They don't really give any concrete examples of why this would be a good practice.

>What is actually going on is the writeline method is calling the ToString method of the class. If you look at the online help, you will see how it references the implicit call to ToString. This is confusing and for readability, I would recommend expicitly calling ToString.
>
>>I have been learning C# thru Deitel's C# book. They have an example that they don't clearly explain the reason for the result.
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>>In a contructor for a class they have:
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>>writeline("Circle 5 constructor: {0}", this );
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>>
>>They explain that "this" implicitly calls the ToString() method of the class. How does the class know that ToString() is the method to call. There are 3 methods in the class. In looking at it, only one class returns a string. Could that be the reason?
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>>Thanks,
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>>Perry