public ucLoanCalculator()
{
InitializeComponent();
LoanPayment.InitInterestRateData(editInterestRate);
LoanPayment.InitTermOfLoan(editTermOfLoan);
LoanPayment.InitStartMonth(editStart);
editLoanAmount.Value = 250000;
lciInfo.Padding = new DevExpress.XtraLayout.Utils.Padding(2, 2, 2, lciCalc.Height);
}
private void gridView1_ShowFilterPopupCheckedListBox(object sender, DevExpress.XtraGrid.Views.Grid.FilterPopupCheckedListBoxEventArgs e)
{
if (e.Column.FieldName == gcMonth.FieldName)
{
foreach (CheckedListBoxItem item in e.CheckedComboBox.Items)
{
item.Description = LoanPayment.GetMonthString(Convert.ToInt32(((DevExpress.XtraGrid.Views.Grid.FilterItem)item.Value).Value), gridControl1.DataSource as List <LoanPayment>);
}
}
}
void Calc()
{
List <LoanPayment> data = LoanPayment.Calculate(LoanAmount, InterestRate, Months, StartMonth, out monthlyPayment);
gridControl1.DataSource = data;
lcInfo.Text = string.Format("<size=+3>Your Monthly Payment<br><size=+4>{0:c}", monthlyPayment);
BeginInvoke(new MethodInvoker(delegate { gcBalance.BestFit(); }));
InterestSeries.DataSource = data;
InterestSeries.SummaryFunction = "SUM([Interest])";
PrincipalSeries.DataSource = data;
PrincipalSeries.SummaryFunction = "SUM([Principal])";
}
private void gridView1_CustomDrawCell(object sender, DevExpress.XtraGrid.Views.Base.RowCellCustomDrawEventArgs e)
{
LoanPayment payment = gridView1.GetRow(e.RowHandle) as LoanPayment;
if (payment == null)
{
return;
}
if (e.Column == gcMonth)
{
e.DisplayText = payment.MonthString;
}
if (e.Column == gcPayment)
{
Rectangle r = e.Bounds;
r.Inflate(-3, -3);
int interestWidth = (int)(r.Width * payment.Interest / payment.MonthlyPayment);
int principalWidth = (int)(r.Width * payment.Principal / payment.MonthlyPayment);
Rectangle interestRect = new Rectangle(r.X, r.Y, interestWidth, r.Height);
Rectangle principalRect = new Rectangle(r.X + interestWidth, r.Y, principalWidth, r.Height);
e.Graphics.FillRectangle(interestBrush, interestRect);
e.Graphics.FillRectangle(principalBrush, principalRect);
using (StringFormat sf = new StringFormat()) {
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Center;
if (e.Graphics.MeasureString(string.Format(GetCellFormat(payment.Interest), payment.Interest), cellFont).Width < interestRect.Width)
{
e.Graphics.DrawString(string.Format(GetCellFormat(payment.Interest), payment.Interest), cellFont, interestForeBrush, interestRect, sf);
}
else
{
e.Graphics.DrawString(string.Format(GetCellFormat(payment.Interest), payment.Interest), cellFont, principalForeBrush, principalRect, sf);
}
sf.Alignment = StringAlignment.Far;
if (e.Graphics.MeasureString(string.Format(GetCellFormat(payment.Principal), payment.Principal), cellFont).Width < principalRect.Width)
{
e.Graphics.DrawString(string.Format(GetCellFormat(payment.Principal), payment.Principal), cellFont, principalForeBrush, principalRect, sf);
}
else
{
e.Graphics.DrawString(string.Format(GetCellFormat(payment.Principal), payment.Principal), cellFont, interestForeBrush, interestRect, sf);
}
}
e.Graphics.DrawRectangle(paymentPen, new Rectangle(interestRect.X, interestRect.Y - 1, (interestRect.Width + principalRect.Width), interestRect.Height + 1));
e.Handled = true;
}
}
public static List <LoanPayment> Calculate(double loanAmount, double interestRate, double months, DateTime startMonth, out double payment)
{
payment = (loanAmount * interestRate) / (1 - Math.Exp((-months) * Math.Log(1 + interestRate)));
payment = LoanPayment.Trunc2(payment);
List <LoanPayment> payments = new List <LoanPayment>();
double balance = loanAmount;
for (int i = 1; i <= Convert.ToInt32(months); i++)
{
LoanPayment lp = new LoanPayment(balance, payment, i, interestRate, startMonth);
balance = lp.Balance;
payments.Add(lp);
if (lp.Balance <= 0)
{
break;
}
}
payments[payments.Count - 1].UpdateBalance();
return(payments);
}
private void gridView1_CustomSummaryCalculate(object sender, DevExpress.Data.CustomSummaryEventArgs e)
{
if (e.SummaryProcess == CustomSummaryProcess.Start)
{
customSum = new PaymentTypeSum();
}
if (e.SummaryProcess == CustomSummaryProcess.Calculate)
{
LoanPayment payment = gridView1.GetRow(e.RowHandle) as LoanPayment;
if (payment != null && e.IsTotalSummary)
{
customSum.AddToSum(payment.Interest, payment.Principal);
}
}
if (e.SummaryProcess == CustomSummaryProcess.Finalize)
{
if (e.IsTotalSummary)
{
e.TotalValue = customSum;
}
}
}
