Chapter 3 |
|
|
Home Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Table of Contents |
Variables, Expressions, and StatementsVariables are names of values contained in memory locations. Variables are named with the InterCap method. You build variable names by joining words or portions of words. Capitalize the first letter of each word or word portion. You can use these arithmetic operations in Visual Basic: exponentiation (^), multiplication (*), division (/), addition (+), and subtraction (-). You can remember the order in which these operations are executed with "Please Excuse My Dear Aunt Sally:" The assignment statement evaluates an expression on the right side of the equal sign and assigns that value to the variable on the left side.
The assignment statement is also used to assign values to properties of objects.
Program break points are set from the toolbar. A break point stops program execution at a particular line. While the program is halted, you can print or change the values of variables from the Debug window. The Single-Step button in the toolbar executes one line of code with each click. After a line is executed, the program halts, allowing you to check and alter values in the Debug window. The Variant type is capable of representing any of the other types. The SetFocus method, a built-in subroutine, shifts the focus from control to control. txtTime.SetFocus shifts the focus to the object named txtTime. |