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 WindowsFormsapplication4{ public partial class Form1 : Form { public Form1() { InitializeComponent();

} PRivate void Form1_Load(object sender, EventArgs e) { this.Text = "一元二次方程求解器"; }

private void button1_Click(object sender, EventArgs e) { A T=new A(); T.a = double.Parse(textBox1.Text); T.b = double.Parse(textBox2.Text); T.c = double.Parse(textBox3.Text); if (T.a == 0) textBox4.Text = string.Format("此為一元一次方程根為 x = {0}", (-T.c / T.b)); else { object box = textBox4; T.Answer(T.a, T.b, T.c, box); } }

} } class A { public double a, b, c; public double Answer(double a, double b, double c, object box) { double x1; double x2; TextBox temp = (TextBox)box; if ((b * b - 4 * a * c) > 0) { x1 = ((-b + Math.Sqrt(b * b - 4 * a * c)) / (2 * a)); x2 = ((-b - Math.Sqrt(b * b - 4 * a * c)) / (2 * a)); temp.Text = String.Format("x1={0},x2={1}", x1, x2);

} else if ((b * b - 4 * a * c) == 0) { x1 = x2 = ((-b + Math.Sqrt(b * b - 4 * a * c)) / (2 * a)); temp.Text = String.Format("x1={0},x2={1}", x1, x2); } else temp.Text = "此參數下的一元二次方程無解";

return 0; }}