Amount that does not change during the course of the program is called a constant (Constant), such as 60, 90, etc.
Declaration of symbolic constants:
Const constant name [As constant type]=expression
For example: Const pi As Single=3.14159 The constant name is pi< /p>
Variable: During the execution of the program, the amount whose value can be changed is called a variable.
(1) Important points to note when naming variables:
① It must start with a letter and cannot start with other numbers or other characters.
② It can only consist of letters, numbers or underscores, and cannot contain decimal points, spaces and other characters.
③The maximum length should not exceed 255 characters.
④VB reserved words cannot be used as variable names, such as statement definers, function names, etc.
⑤VB does not distinguish between uppercase and lowercase letters in variable names. For example, Silly and Silly are the same variable.
(2) Declaration of variables:
Dim
For example: Dim s As Integer defines an integer variable, The variable name is s