Format of the Select Case
Select Case TestExpression
[Case expressionlist1
statementblock]
[Case expressionlist2
statementblock]
[Case Else
statementblock]
End Select
The TestExpression can be any variable or expression, usually a variable.
The Expression List can be
a value Case 1
a list of values Case “red”, “yellow”
a range of values Case 1 to 10
a comparison Case Is > 5
a combination Case 1, 4 to 8, is
> 12
The TestExpression and Expression List should be the same data type.
Each TestExpression is tested in the order they appear. As soon as an expression list satisfies the test expression the statement or statements that follow are executed and control passes to the statement following the End Select.
If TestExpression matches an ExpressionList expression in more than one Case clause, only the statements following the first match are executed.
The Case Else statement is optional. If none of the expression lists satisfy the TestExpression the statement following the Case Else is executed.
Select Case intGrade
Case 100
'equality Implied this assumes maximum value of 100
lblGrade.Text= “Perfect Score”
Case Is > 89
'The word Is
is required with relational operators
lblGrade.Text= “Grade = A”
Case 80 To 89
'specific range identified
lblGrade.Text= “Grade = B”
Case Is > 69
lblGrade.Text= “Grade = C”
Case Is > 59
lblGrade.Text= “Grade = D”
Case Else
lblGrade.Text= “Grade = F”
End Select
intTotGrade += intGrade 'using += operator is same as intTotGrade = intTotGrade + intGrade