Statements and Grammar

This chapter describes:

• What Is a Statement?
• Types of Statements

Notes and samples in this chapter are based Visual Basic 6.0.

What Is a Statement?

A Statement is a basic unit of VB source code. Here is some general rules about a VB statement:

1. One line can not have more than one statement.

2. One statement is usually written in one line. If you want to continue a statement into the second line, you should put (_) at the end of the first line like this:

   statement_part_1 _
      statement_part_2

3. Comments can be entered at the end of a statement proceeded with (') like this:

   statement ' comment

4. Statements are case insensitive. This means that all keywords, variable names and procedure names are case insensitive.

Types of Statements

Like any other generic programming language, VB offers a lots of types of statements. I will only list some commonly uses statement types below:

• Assignment Statement - Assigning values to variables.
• Call Statement - Invoking sub procedures.
• Dim Statement - Defining a variable or an array.
• Do ... Loop Statement - Looping on dynamic conditions.
• Erase Statement - Erasing data from arrays.
• Exit Statement - Terminating loops or procedures.
• For Each ... Next Statement - Looping on every elements of arrays.
• For ... Next Statement - Looping on incremental variables.
• Function Statement - Defining function procedures.
• If Statement - Executing statement blocks conditionally.
• ReDim Statement - Resetting dynamic-size arrays.
• Rem Statement - Writing comments
• Select Case Statement - Executing statement blocks selectively.
• Sub Statement - Defining subroutine procedures.
• While Statement - Looping on dynamic conditions.

Conclusions

• Statements can be continued on the next line with (_) character.
• VB source code is case insensitive.