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:

DimAs

For example: Dim s As Integer defines an integer variable, The variable name is s