Variables and Calculations
You may have noticed that the lessons up to this point haven’t done much with numbers,
dates, text (other than to just display it), or any other pieces of data. They’ve mostly dealt
with controls and their properties, methods, and events.
Although you can do some fairly impressive things with controls alone, most programs also
need to manipulate data. They need to do things like add purchase costs, calculate sales tax,
sort appointments by time, and search text for keywords.
The lessons in this section explain how to perform these kinds of tasks. They explain the vari-
ables that a program uses to represent data in code, and they show how to manipulate variables
to calculate new results.
LESSON 11: Using Variables and Performing Calculations
LESSON 12: Debugging Code
LESSON 13: Understanding Scope
LESSON 14: Working with Strings
LESSON 15: Working with Dates and Times
LESSON 16: Using Arrays and Collections
LESSON 17: Using Enumerations and Structures
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