1 files changed, 139 insertions, 0 deletions
diff --git a/future_value3/FutureValue/frmFutureValue.cs b/future_value3/FutureValue/frmFutureValue.cs
new file mode 100644
index 0000000..4f5c705
--- /dev/null
+++ b/future_value3/FutureValue/frmFutureValue.cs
@@ -0,0 +1,139 @@
+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();
+		}
+
+		// DONE: Declare the rectangular array and the row index here
+		string[,] calculations = new string[10, 4];
+		int row = 0;
+
+		private void btnCalculate_Click(object sender, EventArgs e)
+		{
+			try {
+				if (IsValidData()) {
+					decimal monthlyInvestment =
+						Convert.ToDecimal(txtMonthlyInvestment.Text);
+					decimal yearlyInterestRate =
+						Convert.ToDecimal(txtInterestRate.Text);
+					int years = Convert.ToInt32(txtYears.Text);
+
+					int months = years * 12;
+					decimal interestRateMonthly = yearlyInterestRate / 12 / 100;
+
+					decimal futureValue = CalculateFutureValue(
+						monthlyInvestment, interestRateMonthly, months);
+					txtFutureValue.Text = futureValue.ToString("c");
+					txtMonthlyInvestment.Focus();
+
+					// DONE: Add the calculation to the rectangular array here
+					calculations[row, 0] = monthlyInvestment.ToString("c");
+					calculations[row, 1] = yearlyInterestRate.ToString("p");
+					calculations[row, 2] = years.ToString();
+					calculations[row, 3] = futureValue.ToString("c");
+					row++;
+				}
+			}
+			catch (Exception ex) {
+				MessageBox.Show(ex.Message + "\n\n" +
+					ex.GetType().ToString() + "\n" +
+					ex.StackTrace, "Exception");
+			}
+		}
+
+		public bool IsValidData()
+		{
+			bool success = true;
+			string errorMessage = "";
+
+			// Validate the Monthly Investment text box
+			errorMessage += IsDecimal(txtMonthlyInvestment.Text, txtMonthlyInvestment.Tag.ToString());
+			errorMessage += IsWithinRange(txtMonthlyInvestment.Text, txtMonthlyInvestment.Tag.ToString(), 1, 1000);
+
+			// Validate the Yearly Interest Rate text box
+			errorMessage += IsDecimal(txtInterestRate.Text, txtInterestRate.Tag.ToString());
+			errorMessage += IsWithinRange(txtInterestRate.Text, txtInterestRate.Tag.ToString(), 1, 20);
+
+			// Validate the Number of Years text box
+			errorMessage += IsInt32(txtYears.Text, txtYears.Tag.ToString());
+			errorMessage += IsWithinRange(txtYears.Text, txtYears.Tag.ToString(), 1, 40);
+
+			if (errorMessage != "") {
+				success = false;
+				MessageBox.Show(errorMessage, "Entry Error");
+			}
+			return success;
+		}
+
+		public static string IsPresent(string value, string name)
+		{
+			string msg = "";
+			if (value == "")
+				msg += name + " is a required field.\n";
+			return msg;
+		}
+
+		public static string IsDecimal(string value, string name)
+		{
+			string msg = "";
+			if (!Decimal.TryParse(value, out _))
+				msg += name + " must be a valid decimal value.\n";
+			return msg;
+		}
+
+		public static string IsInt32(string value, string name)
+		{
+			string msg = "";
+			if (!Int32.TryParse(value, out _))
+				msg += name + " must be a valid integer value.\n";
+			return msg;
+		}
+
+		public static string IsWithinRange(string value, string name, decimal min, decimal max)
+		{
+			string msg = "";
+			if (Decimal.TryParse(value, out decimal number))
+				if (number < min || number > max)
+					msg += name + " must be between " + min + " and " + max + ".\n";
+			return msg;
+		}
+		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)
+		{
+			// DONE: Display the rectangular array in a dialog box here
+			string msg = "Inv/Mo\tRate\tYears\tFuture Values\n";
+			if (row > 0) {
+				for (int i = 0; i < row; i++) {
+					for (int j = 0; j < 4; j++)
+						msg += calculations[i, j] + "\t";
+					msg += "\n";
+				}
+				MessageBox.Show(msg, "Future Value Calculations");
+			}
+			this.Close();
+		}
+
+	}
+}