passing a class to method

Hi,
I'm a relative noob to all this and thought I'd ask a noob question.
I have a repeater that uses the ItemDataBind method.  Within I cast the row back to a class, say my class.  It looks like this:
CategorySummary cs = (CategorySummary)e.Item.DataItem;
I then call some methods (static) to customise the data in cs.
The question I have is, generally, is it better to pass individual properties, is it fundamentally wrong to pass an entire class or does it not matter.
For instance:
MyMethod(cs) instead of MyMethod(cs.MyName, cs.MyAge)
 
Thanks
 
John
 
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