Computer Programming Concepts and Visual Basic David I. Schneider

Dim yrs As String, pay As Single, pymnt As String
‘Display monthly payment amount
mRate = yearlyRate / 12 ‘monthly rate
prn = FormatCurrency(prin)
apr = FormatNumber(yearlyRate * 100)
yrs = FormatNumber(numMs / 12, 0)
pay = Payment(prin, mRate, numMs)
pymnt = FormatCurrency(pay)
picDisp.Cls
picDisp.Print “The monthly payment for a “& prn & “loan at “
picDisp.Print apr & “% annual rate of interest for “;
picDisp.Print yrs & “years is “& pymnt
End Sub
COMMENTS
1. Tasks 3.1 and 3.2 are performed by functions. Using functions to compute these
quantities simplifies the computations in ShowAmortSched.
2. Because the payment was rounded up to the nearest cent, it is highly likely that
the payment needed in the final month to pay off the loan will be less than the
normal payment. For this reason, ShowAmortSched checks if the balance of the
loan (including interest due) is less than the regular payment, and if so, makes
appropriate adjustments.
3. The standard formula for computing the monthly payment cannot be used if
either the interest rate is zero percent or the loan duration is zero months.
Although both of these situations do not represent reasonable loan parameters,
provisions are made in the function Payment so that the program can handle
these esoteric situations.
SUMMARY
1. A Do loop repeatedly executes a block of statements either as long as or until a
certain condition is true. The condition can be checked either at the top of the
loop or at the bottom.
2. The EOF function tells us if we have read to the end of a file.
3. As various items of data are processed by a loop, a counter can be used to keep
track of the number of items, and an accumulator can be used to sum numerical
values.
4. A flag is a Boolean variable, used to indicate whether or not a certain event has
occurred.
5. A For...Next loop repeats a block of statements a fixed number of times. The
control variable assumes an initial value and increments by one after each pass
through the loop until it reaches the terminating value. Alternative increment
values can be specified with the Step keyword.
PROGRAMMING PROJECTS
1. Write a program to display a company’s payroll report in a picture box. The program
should read each employee’s name, hourly rate, and hours worked from a
Programming Projects 153