Computer Programming Concepts and Visual Basic David I. Schneider

EXAMPLE 2
The following program uses the file STAFF.TXT in Figure 2-24 to compute weekly pay. Notice that the
variables in the Input # statement are the same types (String, Single, Single) as the constants in each line
of the file.
Private Sub cmdCompute_Click()
Dim nom As String, wage As Single, hrs As Single
picPay.Cls
Open “STAFF.TXT” For Input As #1
Input #1, nom, wage, hrs
picPay.Print nom; hrs * wage
Input #1, nom, wage, hrs
picPay.Print nom; hrs * wage
Close #1
End Sub
[Run, and then click the command button. The following will be displayed in the picture box.]
Mike Jones 257.25
John Smith 222.75
In certain situations, we must read the data in a file more than once. This is accomplished
by closing the file and reopening it. After a file is closed and then reopened, subsequent
Input # statements begin reading from the first entry of the file.
EXAMPLE 3
The following program takes the average annual amounts of money spent by single-person households for
several categories and converts these amounts to percentages. The data are read once to compute the total
amount of money spent and then read again to calculate the percentage for each category. Note: These
figures were compiled for the year 1995 by the Bureau of Labor Statistics.
COSTS.TXT consists of the following four lines:
“Transportation”, 3887
“Housing”, 7643
“Food”, 3017
“Other”, 7804
Private Sub cmdCompute_Click()
Dim total As Single, category As String, amount As Single
Open “COSTS.TXT” For Input As #1
picPercent.Cls
total = 0
Input #1, category, amount
total = total + amount
Input #1, category, amount
total = total + amount
Input #1, category, amount
total = total + amount
Input #1, category, amount
total = total + amount
Close #1
Open “COSTS.TXT” For Input As #1
Input #1, category, amount
picPercent.Print category; amount / total
Input #1, category, amount
picPercent.Print category; amount / total
Input #1, category, amount
Input and Output 51