1 files changed, 128 insertions, 0 deletions
diff --git a/future_value2/FutureValue/frmFutureValue.cs b/future_value2/FutureValue/frmFutureValue.cs
new file mode 100644
index 0000000..f301573
--- /dev/null
+++ b/future_value2/FutureValue/frmFutureValue.cs
@@ -0,0 +1,128 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Data;
+using System.Drawing;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Forms;
+
+namespace FutureValue
+{
+	public partial class frmFutureValue : Form
+	{
+		public frmFutureValue()
+		{
+			InitializeComponent();
+		}
+
+		private bool IsDecimal(string txt, string name)
+		{
+			if (Decimal.TryParse(txt, out _))
+				return true;
+			MessageBox.Show(name + " must be a decimal");
+			return false;
+		}
+
+		private bool IsInt32(string txt, string name)
+		{
+			if (Int32.TryParse(txt, out _))
+				return true;
+			MessageBox.Show(name + " must be an integer");
+			return false;
+		}
+
+		private bool IsWithinRange(string txt, string name, decimal min, decimal max)
+		{
+			if (Decimal.TryParse(txt, out decimal i))
+				if (i < min || i > max) {
+					MessageBox.Show(name + " must be in the range of "
+					+ min + " to " + max + "\n");
+					return false;
+				}
+			return true;
+		}
+
+		private bool IsValidData()
+		{
+			bool valid = true;
+
+			if(!IsDecimal(txtMonthlyInvestment.Text,
+				txtMonthlyInvestment.Name))
+				valid = false;
+			if(!IsWithinRange(txtMonthlyInvestment.Text,
+				txtMonthlyInvestment.Name, 0, 10000))
+				valid = false;
+
+			if(!IsDecimal(txtInterestRate.Text,
+				txtInterestRate.Name))
+				valid = false;
+			if(!IsWithinRange(txtInterestRate.Text,
+				txtInterestRate.Name, 0, 10000))
+				valid = false;
+
+			if(!IsInt32(txtYears.Text,
+				txtYears.Name))
+				valid = false;
+			if(!IsWithinRange(txtYears.Text,
+				txtYears.Name, 0, 10000))
+				valid = false;
+
+			return valid;
+		}
+
+		private void btnCalculate_Click(object sender, EventArgs e)
+		{
+			try {
+				if (!IsValidData())
+					return;
+
+				decimal monthlyInvestment = Convert.ToDecimal(txtMonthlyInvestment.Text);
+				decimal yearlyInterestRate = Convert.ToDecimal(txtInterestRate.Text);
+				int years = Convert.ToInt32(txtYears.Text);
+
+				int months = years * 12;
+				decimal monthlyInterestRate = yearlyInterestRate / 12 / 100;
+
+				decimal futureValue = this.CalculateFutureValue(
+					monthlyInvestment, monthlyInterestRate, months);
+				txtFutureValue.Text = futureValue.ToString("c");
+				txtMonthlyInvestment.Focus();
+
+				/* throw new Exception("There was an unknown error"); */
+			}
+			/* catch (FormatException) {
+				MessageBox.Show("Invalid format: Try entering " +
+					"numbers between 1 and 9999", "Entry Error");
+			}
+			catch (OverflowException) {
+				MessageBox.Show("Overflow Error: Try entering"
+					+ "smaller numbers", "Entry Error");
+			} */
+			catch (Exception ex){
+				MessageBox.Show(ex.Message + "\n" +
+				ex.GetType().ToString() +  "\n" +
+				ex.StackTrace, "Entry Error");
+			}
+		}
+
+		private decimal CalculateFutureValue(decimal monthlyInvestment,
+			decimal monthlyInterestRate, int months)
+		{
+			decimal futureValue = 0m;
+			for (int i = 0; i < months; i++)
+			{
+				futureValue = (futureValue + monthlyInvestment)
+							* (1 + monthlyInterestRate);
+			}
+			return futureValue;
+		}
+
+		private void btnExit_Click(object sender, EventArgs e)
+		{
+			this.Close();
+		}
+
+	}
+}