The document discusses comparison operators and their usage in Visual Basic. It explains that comparison operators are used to compare data values and return true or false results. Some key comparison operators covered include >, <, =, >=, <=, and <>. The document also discusses how comparison operators are used within IF and SELECT CASE statements to conditionally execute blocks of code based on the results of comparisons.

1. Working with
Comparison
Operators
Jesselle Capa
Charles Justine Bool

2. Comparison Operators
Operators that compare data values
to produce true or false results.
ASCII
Contains a list of characters with
corresponding unique numeric
representation

3. Comparison Operators
Operator Usage Description
> lblSales.Caption > The greater than operator return True Only
Goal if the value on the right.
< Pay < 2000.0 The less than operator return True if the
value on the left of < is less than the value
on the right.
= Age = Limit The equal to operator return True if the
value on the both sides of = are equal.
>= FirstName >= The greater than or equal to operator
“Mike” return True if the value on the left of >= is
greater than or equal to the value on the
right.
<= Num <= The less than or equal to operator return
lblAmt.Caption True if the value on the left of <= is less
than or equal to the value on the right.
<> txtAns.text<> The not equal to operator return True if the
“Yes” value on the left of <> is unequal to the
value on the right.

4. Relationship Results
Relation Result
2>1 True
3<3 False
5 > 10 True
“Apple” <= “Orange” True
“Macdonald “ < “Mc Donald” True
0 >=0 True
0 <=0 True
1 <>2 True
2 >=3 False

5. Working with If Statement
 The If statement provides logic for the
application, w/c analyzes data and makes
decisions based on the analysis.
 The If statement uses comparison operators
to test data values and performs one of two
possible actions based on the results of the
comparison‟s test.
 Without the If statement, the application
code will sequentially execute . Meaning , one
statement is executed after another.

6. The If statement is usually
written in the following
format:
If comparisonTest Then
One or more statements
End If

7. If Statement and Comparison
 Keep in mind that the body of the If
statement executes based on the results of
the comparison test. The statement executes
if the results is true. Otherwise , the rest of
the application executes as usual and the If
statement will be skipped.
 Data that are entered into a text box control
is treated as a Variant data type . When
arithmetic is performed with a Variant with
data type that holds a numeric value . Visual
Basic will convert such data to a number for
the calculation purposes.

8. The If statement's Else Branching
 The If statement with Else is usually written in
the following format:
If comparisontest Then
one or more statements
Else
one or more statements
End If

9. Compound Comparison with the
Logical Operators
Operator Usage Description
And If (A > B) And (C < Returns True if both sides
D) of the And are true.
Or If (A > B) Or (C < Returns True if either side
D) of the Or is true.
Not If Not (strAns = Returns the opposite true
“Yes”) or false result.

10. Example :
Private Sub cmdGetStudentGrade_Click()
„Code for Generating Student's Grade
„Declare Variables
Dim percent As Integer, studentmark As String
„Clear text Box
txtGrade.Text = ""
„Get Students Mark from inputbox
percent = InputBox("Enter Students
Percent")

11. 'Begin if statement
If percent >= 50 And percent < 60 Then
studentmark = "C"
Else percent >= 60 And percent < 70 Then
studentmark = "B"
Else percent >= 70 Then
studentmark = "A"
Else
studentmark = "FAIL"
End If
'Display Output
txtGrade.Text = studentmark
End Sub

15. Nesting If-Else Statements
If (intAge = 5) Then
lblTitle.Caption = “Kindergarten”
Else
If (intAge = 6) Then
lblTitle.Caption = “1st Grade”
Else
If (intAge = 7) Then
lblTitle.Caption = “2nd Grade”

16. If (intAge = 8) Then
lblTitle.Caption = “3rd Grade”
Else
If (intAge = 9) Then
lblTitle.Caption = “4th Grade”
Else
If (intAge = 10) Then
lblTitle.Caption = “5th Grade”
Else
If (intAge = 11) Then
lblTitle.Caption = “6th Grade”
Else

17. lblTitle.Caption = "Advanced"
End If
End If
End If
End If
End If
End If
End If

18. Using Select Case Statement
 The Select Case Statement handles multiple –
choice conditions better than If-Else . When
several choices are possible , programmers
usually use Select Case as a substitute for
long , nested If-Else , but you may find out
that it is easier to code and to maintain .
However , you must avoid using the Select
Case if you will have a simple If or If-
Else for the code , unless you need to
compare against more than two values .
Otherwise , stick with the simple If and If-
Else statements

19. Select Case intAge
Case 5 : lblTitle.Caption = "Kindergarten"
Case 6 : lblTitle.Caption = "1st Grade"
Case 7 : lblTitle.Caption = "2nd Grade"
Case 8 : lblTitle.Caption = "3rd Grade"
Case 9 : lblTitle.Caption = "4th Grade"
Case 10 : lblTitle.Caption = "5th Grade
Case 11 : lblTitle.Caption = "6th Grade
Case Else : lblTitle.Caption = "Advanced"
End Select

20. 3 Select Case Optional Formats:
Select Case Expressions
Case Is Relation :
One or more Statements
Case Is Relation :
One or more Statements
[Case Is Relation :
One or more Statements]
[Case Is Relation :
One or more Statements]
End Else

21. Select Case Expressions
Case Value
One or more Visual Basic Statements
Case Value
One or more Visual Basic Statements
[Case Value
One or more Visual Basic Statements]
[Case Value
One or more Visual Basic Statements]
End Else

22. Select Case Expressions
Case expr1 To expr2 :
One or more Visual Basic Statements
Case expr1 To expr2 :
One or more Visual Basic Statements
[Case expr1 To expr2 :
One or more Visual Basic Statements]
[Case Else :
One or more Visual Basic Statements]
End Else