public void TotalMoneyPaidTest()
{
PayoffModel model = new PayoffModel(259000, 4, 30, 0, 1236.51);
TotalInterest save = new TotalInterest(model);
double total = save.Algorithm();
Assert.Equal(445143.60, total);
}
public void TotalMoneySavedTest()
{
PayoffModel model = new PayoffModel(259000, 4, 30, 25, 1236.51);
TotalInterest save = new TotalInterest(model);
double total = save.Algorithm();
Assert.Equal(16074.63, model.TotalMoneySaved);
}
public override string ToString()
{
return($"{Term} months (effective {AnnualPercentageRate}, nominal {NominalRate}): monthly {MonthlyPayment.ToString()}, total {TotalCost.ToString()}, interest {TotalInterest.ToString()}");
}
private void calculateBTN_Click(object sender, EventArgs e)
{
try
{
//declaring variables
double PurchasePrice, DownPymt, Rate, MonthlyPymt, LoanAmt, Percent, TotalInterest;
int Term;
//parsing text
PurchasePrice = double.Parse(inPurchasePriceTB.Text);
DownPymt = double.Parse(inDownPymtTB.Text);
Rate = double.Parse(rateTB.Text) / 100;
Term = int.Parse(termTB.Text);
Percent = double.Parse(inDownPymtTB.Text) / 100;
//Checking Percent of purchase price or dollar value
if (percentRB.Checked)
{
DownPymt = PurchasePrice * Percent;
}
else if (dollarsRB.Checked)
{
DownPymt = double.Parse(inDownPymtTB.Text);
}
// checking Years or Months
if (yearsRB.Checked)
{
Term = Term * 12;
}
else if (monthRB.Checked)
{
Term = int.Parse(termTB.Text);
}
// assigning formula variables
double interest = Rate / 12;
LoanAmt = PurchasePrice - DownPymt;
MonthlyPymt = LoanAmt * ((interest * (Math.Pow(1 + interest, Term))) /
(Math.Pow(1 + interest, Term) - 1));
TotalInterest = (MonthlyPymt * Term) - LoanAmt;
double totalAmtPaid = MonthlyPymt * Term;
// Display the answers
loanAmtTB.Text = LoanAmt.ToString();
monthlyPymtTB.Text = MonthlyPymt.ToString("n2");
totalInterestPaidTB.Text = TotalInterest.ToString("n2");
totalAmtPaidTB.Text = totalAmtPaid.ToString("n2");
}
catch (Exception)
{
MessageBox.Show("Something is WRONG with your figures");
}
}
