Question

C#程序设计 输入三角形三边长,并计算的周长和面积

Answer 1

前台有五个TextBox,分别是FirstTxt,SecondTxt,ThridTxt(代表a,b,c三边长),areaTxt,aroundTxt(代表面积,周长),一个计算的Button.对输入进行了控制,对是否可形成三角形进行了控制,最终计算.计算三角形面积用的是海伦公式.下面是源码：using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Text.RegularExpressions;using System.Windows.Forms;namespace triangle{public partial class Form1 : Form{public Form1(){InitializeComponent();}public double Alength;public double Blength;public double Clength;private Regex reg = new Regex("^(0|[1-9][0-9]*)$");//用于检测的正则表达式//只能输入0或者非0开头的数字private void Form1_Load(object sender, EventArgs e){this.FirstTxt.Text = "1";this.SecondTxt.Text = "1";this.ThirdTxt.Text ="1";}private bool TestTriangle(double a,double b,double c){//测试是否能形成三角形double result1 = a + b;double result2 = a + c;double result3 = b + c;if (result1>c&&result2>b&&result3>a){return true;}else{return false;}}private double CountArea(double a,double b,double c){//计算面积double p = (a+b+c)/2;double area = Math.Sqrt(p * (p - a) * (p - b) * (p - c));return area;}private double CountAround(double a,double b,double c){//计算边长return a + b + c;}private void count_Click(object sender, EventArgs e){ if (reg.IsMatch(this.FirstTxt.Text)&®.IsMatch(this.SecondTxt.Text)&®.IsMatch(this.ThirdTxt.Text)){Alength = Double.Parse(this.FirstTxt.Text);Blength = Double.Parse(this.SecondTxt.Text);Clength = Double.Parse(this.ThirdTxt.Text);if (TestTriangle(Alength, Blength, Clength)){ this.aroundtxt.Text = CountAround(Alength, Blength, Clength).ToString(); this.areatxt.Text = CountArea(Alength, Blength, Clength).ToString();}else{ MessageBox.Show("当前不形成三角形!");}}else{MessageBox.Show("请输入合法的边长值!");}}}}