自己动手写计算器v1.0
今天突发奇想,想着看了还几个设计模式了,倒不如写点东西来实践它们。发现计算器这种就比较合适,打算随着设计模式的学习,会对计算器不断的做改进。
包括功能的增加和算法的改进。初学者难免犯错,希望大家不吝指教。
计算器V1.0:主要实现了计算器最常见的加减乘除功能,同时还有一个特殊功能,例如:我们执行完1+2后,如果点击等号,会执行加法运算输出结果。但我们如果点击的是运算符(如-),那么不仅会执行加法运算,还会将-号放置到执行结果后,表示这次执行的将会是减法运算。
代码:Operator类负责使用简单工厂模式来生成加减乘除运算。
Form窗体后台代码:
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 计算器 { public partial class Form1 : Form { //简述:变量集中声明处 StringBuilder num1 = new StringBuilder(); StringBuilder num2 = new StringBuilder(); public void CheckTextbox(string num) { StringBuilder str = new StringBuilder(); if (this.textBox1.Text != "") { str.Append(this.textBox1.Text); str.Append(num); this.textBox1.Text = str.ToString(); } else { this.textBox1.Text = num; } } //简述:输入运算符。 2016-5-13 张杨 public void CheckYunSuan(string myOperator) { StringBuilder str = new StringBuilder(); if (this.textBox1.Text != "") { if (textBox1.Text.Contains("+") || textBox1.Text.Contains("-") || textBox1.Text.Contains("*") || textBox1.Text.Contains("/")) { ShowResult(); } str.Append(this.textBox1.Text); str.Append(myOperator); this.textBox1.Text = str.ToString(); } else { this.textBox1.Text = myOperator; } } public Form1() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { CheckTextbox("1"); } private void button2_Click(object sender, EventArgs e) { CheckTextbox("2"); } private void button3_Click(object sender, EventArgs e) { CheckTextbox("3"); } private void button4_Click(object sender, EventArgs e) { CheckTextbox("4"); } private void button5_Click(object sender, EventArgs e) { CheckTextbox("5"); } private void button6_Click(object sender, EventArgs e) { CheckTextbox("6"); } private void button7_Click(object sender, EventArgs e) { CheckTextbox("7"); } private void button8_Click(object sender, EventArgs e) { CheckTextbox("8"); } private void button9_Click(object sender, EventArgs e) { CheckTextbox("9"); } //简述:下面的为加减乘除功能。 //2016-5-13 张杨 private void button10_Click(object sender, EventArgs e) { CheckYunSuan("+"); } private void button11_Click(object sender, EventArgs e) { CheckYunSuan("-"); } private void button12_Click(object sender, EventArgs e) { CheckYunSuan("*"); } private void button13_Click(object sender, EventArgs e) { CheckYunSuan("/"); } private void button14_Click(object sender, EventArgs e) { this.textBox1.Text = String.Empty; } //简述:判断字符是否为运算符。 2016-5-13 张杨 public bool isOperator(char key) { if (key == '+' || key == '-' || key == '*' || key == '/') { return true; } else { return false; } } //简述:计算结果。 2016-5-13 张杨 private void ShowResult() { string strText = this.textBox1.Text; char myOperator = 'A'; int flag = 0; string result = ""; foreach (char key in strText) { if (isOperator(key)) { flag = 1; myOperator = key; continue; } else { switch (flag) { case 0: num1.Append(key); break; case 1: num2.Append(key); break; } } } result = OperatorFactory.GetResult(myOperator, double.Parse(num1.ToString()), double.Parse(num2.ToString())); num1 = num1.Remove(0, num1.Length); num2 = num2.Remove(0, num2.Length); this.textBox1.Text = result; } private void button15_Click(object sender, EventArgs e) { ShowResult(); } } }
重点来了,Operator类:
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace 计算器 { //简述:加减乘除处理类,采用了简单工厂模式。 2016-5-13 张杨 class Operator { public virtual string GetResult(double num1, double num2) { return "error"; } } public class OperatorFactory { static Operator myOperator=new Operator(); public static string GetResult(char key,double num1,double num2) { switch (key) { case '+': myOperator = new plusOperator(); break; case '-': myOperator = new jianOperator(); break; case '*': myOperator = new chenOperator(); break; case '/': myOperator = new chuOperator(); break; } return myOperator.GetResult(num1,num2); } } class plusOperator : Operator { public override string GetResult(double num1, double num2) { return (num1 + num2).ToString(); } } class jianOperator : Operator { public override string GetResult(double num1, double num2) { return (num1 - num2).ToString(); } } class chenOperator : Operator { public override string GetResult(double num1, double num2) { return (num1 * num2).ToString(); } } class chuOperator : Operator { public override string GetResult(double num1, double num2) { if (num2 == 0) { return "除数不能为0"; } else { return (num1 / num2).ToString(); } } } }
运行结果: