3. 數值轉換程式

namespace Q3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            Close();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            var n = double.Parse(textBox1.Text);
            if (n > Math.Pow(2, 15) ||
                n < -Math.Pow(2, 15) - 1)
            {
                textBox2.Text = "overflow";
                return;
            }
            string k = n < 0 ? "1" : "0";
            k += Convert.ToString((int)Math.Abs(n), 2).PadLeft(15, '0');

            k += ".";
            double digit = Math.Abs(n) - (int)Math.Abs(n);
            while (k.Length < 25)
            {
                digit *= 2;
                k += digit >=1 ? "1" : "0";
                if (digit >= 1) digit--;
            }
            textBox2.Text = k;
        }
    }
}