古典MVCなBMI計算アプリ

TraditionalMVCForm.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace BMICalculator
{
  public partial class TraditionalMVCForm : BaseForm
  {
    class Model
    {
      public double Height { get; set; }
      public double Weight { get; set; }

      public event EventHandler<EventArgs> BmiChanged;

      private double bmi;
      public double Bmi
      {
        get
        {
          return bmi;
        }
        set
        {
          if (bmi != value)
          {
            bmi = value;

            if (BmiChanged != null)
            {
              BmiChanged(this, EventArgs.Empty);
            }
          }
        }
      }

      public void Calculate()
      {
        Bmi = Weight / Math.Pow(Height * 0.01, 2);
      }
    }

    class Controller
    {
      private Model model;
      public Controller(Model model)
      {
        this.model = model;
      }

      public void Calculate(string height, string weight)
      {
        double oHeight;
        if (!double.TryParse(height, out oHeight))
        {
          return;
        }
        double oWeight;
        if (!double.TryParse(weight, out oWeight))
        {
          return;
        }

        model.Height = oHeight;
        model.Weight = oWeight;

        model.Calculate();
      }
    }

    private Model model;
    private Controller controller;
    public TraditionalMVCForm()
    {
      InitializeComponent();

      model = new Model();
      model.BmiChanged += (sender, e) =>
        {
          bmiTextBox.Text = model.Bmi.ToString("f2");

          if (model.Bmi < 18d)
          {
            bmiTextBox.BackColor = Color.White;
          }
          else if (model.Bmi < 22d)
          {
            bmiTextBox.BackColor = Color.Yellow;
          }
          else if (model.Bmi < 24d)
          {
            bmiTextBox.BackColor = Color.Orange;
          }
          else
          {
            bmiTextBox.BackColor = Color.Red;
          }
        };

      controller = new Controller(model);
    }

    private void calculateButton_Click(object sender, EventArgs e)
    {
      controller.Calculate(heightTextBox.Text, weightTextBox.Text);
    }
  }
}