简单计算器

  1 using System;
  2 using System.Collections.Generic;
  3 using System.ComponentModel;
  4 using System.Data;
  5 using System.Drawing;
  6 using System.Linq;
  7 using System.Text;
  8 using System.Threading.Tasks;
  9 using System.Windows.Forms;
 10 
 11 namespace 计算器
 12 {
 13     public partial class Counter : Form
 14     {
 15         public Counter()
 16         {
 17             InitializeComponent();
 18         }
 19         //设置全局变量
 20         //加减乘除运算符
 21         string Operator;
 22         //前数值
 23         decimal FrontValue;
 24         //后数值
 25         decimal BehindValue;
 26         //判断已有小数点
 27         bool AlreadyPoint=false;
 28         //判断已等于
 29         bool AlreadyEqual = false;
 30 
 31         private void Counter_Load(object sender, EventArgs e)
 32         {
 33             lblShow.Text = "";
 34         }
 35 
 36         private void btnZero_Click(object sender, EventArgs e)
 37         {
 38             if (AlreadyEqual == true)
 39             {
 40                 txtShow.Text = "";
 41                 lblShow.Text = "";
 42                 AlreadyEqual = false;
 43             }
 44             txtShow.Text += 0;
 45             lblShow.Text += 0;
 46         }
 47 
 48         private void btnOne_Click(object sender, EventArgs e)
 49         {
 50             if (AlreadyEqual == true)
 51             {
 52                 txtShow.Text = "";
 53                 lblShow.Text = "";
 54                 AlreadyEqual = false;
 55             }
 56             txtShow.Text += 1;
 57             lblShow.Text += 1;
 58         }
 59 
 60         private void btnTwo_Click(object sender, EventArgs e)
 61         {
 62             if (AlreadyEqual == true)
 63             {
 64                 txtShow.Text = "";
 65                 lblShow.Text = "";
 66                 AlreadyEqual = false;
 67             }
 68             txtShow.Text += 2;
 69             lblShow.Text += 2;
 70         }
 71 
 72         private void btnThree_Click(object sender, EventArgs e)
 73         {
 74             if (AlreadyEqual == true)
 75             {
 76                 txtShow.Text = "";
 77                 lblShow.Text = "";
 78                 AlreadyEqual = false;
 79             }
 80             txtShow.Text += 3;
 81             lblShow.Text += 3;
 82         }
 83 
 84         private void btnFour_Click(object sender, EventArgs e)
 85         {
 86             if (AlreadyEqual == true)
 87             {
 88                 txtShow.Text = "";
 89                 lblShow.Text = "";
 90                 AlreadyEqual = false;
 91             }
 92             txtShow.Text += 4;
 93             lblShow.Text += 4;
 94         }
 95 
 96         private void btnFive_Click(object sender, EventArgs e)
 97         {
 98             if (AlreadyEqual == true)
 99             {
100                 txtShow.Text = "";
101                 lblShow.Text = "";
102                 AlreadyEqual = false;
103             }
104             txtShow.Text += 5;
105             lblShow.Text += 5;
106         }
107 
108         private void btnSix_Click(object sender, EventArgs e)
109         {
110             if (AlreadyEqual == true)
111             {
112                 txtShow.Text = "";
113                 lblShow.Text = "";
114                 AlreadyEqual = false;
115             }
116             txtShow.Text += 6;
117             lblShow.Text += 6;
118         }
119 
120         private void btnSeven_Click(object sender, EventArgs e)
121         {
122             if (AlreadyEqual == true)
123             {
124                 txtShow.Text = "";
125                 lblShow.Text = "";
126                 AlreadyEqual = false;
127             }
128             txtShow.Text += 7;
129             lblShow.Text += 7;
130         }
131 
132         private void btnEight_Click(object sender, EventArgs e)
133         {
134             if (AlreadyEqual == true)
135             {
136                 txtShow.Text = "";
137                 lblShow.Text = "";
138                 AlreadyEqual = false;
139             }
140             txtShow.Text += 8;
141             lblShow.Text += 8;
142         }
143 
144         private void btnNine_Click(object sender, EventArgs e)
145         {
146             if (AlreadyEqual == true)
147             {
148                 txtShow.Text = "";
149                 lblShow.Text = "";
150                 AlreadyEqual = false;
151             }
152             txtShow.Text += 9;
153             lblShow.Text += 9;
154         }
155 
156         private void btnPoint_Click(object sender, EventArgs e)
157         {
158             if (AlreadyEqual == true)
159             {
160                 txtShow.Text = "";
161             }
162             if (txtShow.Text != "" && AlreadyPoint==false)
163             {
164                 AlreadyPoint = true;
165                 txtShow.Text += ".";
166             }
167         }
168         //加
169         private void btnAdd_Click(object sender, EventArgs e)
170         {
171             if (txtShow.Text != "")
172             {
173                 FrontValue += decimal.Parse(txtShow.Text);
174                 txtShow.Text = "";
175                 lblShow.Text += " + ";
176                 Operator = "add";
177                 AlreadyPoint = false;
178             }
179         }
180         //减
181         private void btnMinus_Click(object sender, EventArgs e)
182         {
183             if (txtShow.Text != "")
184             {
185                 FrontValue += decimal.Parse(txtShow.Text);
186                 txtShow.Text = "";
187                 lblShow.Text += " - ";
188                 Operator = "Minus";
189                 AlreadyPoint = false;
190             }
191         }
192         //乘
193         private void btnMultiply_Click(object sender, EventArgs e)
194         {
195             if (txtShow.Text != "")
196             {
197                 FrontValue += decimal.Parse(txtShow.Text);
198                 txtShow.Text = "";
199                 lblShow.Text += " * ";
200                 Operator = "Multiply";
201                 AlreadyPoint = false;
202             }
203         }
204         //除
205         private void btnDivided_Click(object sender, EventArgs e)
206         {
207             if (txtShow.Text != "")
208             {
209                 FrontValue += decimal.Parse(txtShow.Text);
210                 txtShow.Text = "";
211                 lblShow.Text += " / ";
212                 Operator = "Divided";
213                 AlreadyPoint = false;
214             }
215         }
216         //等于
217         private void btnEqual_Click(object sender, EventArgs e)
218         {
219             switch(Operator)
220             {
221                 case "add":
222                 BehindValue = FrontValue + decimal.Parse(txtShow.Text);
223                 break;
224                 case "Minus":
225                 BehindValue = FrontValue - decimal.Parse(txtShow.Text);
226                 break;
227                 case "Multiply":
228                 BehindValue = FrontValue * decimal.Parse(txtShow.Text);
229                 break;
230                 case "Divided":
231                 BehindValue = FrontValue / decimal.Parse(txtShow.Text);
232                 break;
233             }
234             txtShow.Text = BehindValue.ToString();
235             FrontValue = 0;
236             AlreadyEqual = true;
237             AlreadyPoint = false;
238             lblShow.Text = txtShow.Text;
239         }
240         //CE清除当前数
241         private void btnCE_Click(object sender, EventArgs e)
242         {
243             txtShow.Text = "";
244             //清除功能对lblShow缺失，没想到好方法
245             lblShow.Text = "";
246         }
247         //C全清
248         private void btnC_Click(object sender, EventArgs e)
249         {
250             txtShow.Text = "";
251             lblShow.Text = "";
252             //加减乘除运算符
253             Operator="";
254             //前数值
255             FrontValue=0;
256             //后数值
257             BehindValue=0;
258             //判断已有小数点
259             AlreadyPoint = false;
260             //判断已等于
261             AlreadyEqual = false;
262         }
263         //回退功能
264         private void btnFallback_Click(object sender, EventArgs e)
265         {
266             if (txtShow.Text != "")
267             {
268                 txtShow.Text = txtShow.Text.Substring(0, txtShow.Text.Length-1);
269                 lblShow.Text = lblShow.Text.Substring(0, lblShow.Text.Length - 1);
270             }
271         }
272     }
273 }