1 namespace WindowsFormsApplication6
2 {
3 public partial class Form1 : Form
4 {
5 //存储上次点击了什么按钮，0代表什么都没有点击，1代表数字按钮，2代表点击了运算符
6 private int prev = 0;
7 //存储计算的中间结果
8 private decimal zjjg = 0;
9 //记录上次按得什么运算符
10 private string prevysf = "+";
11
12 public Form1()
13 {
14 InitializeComponent();
15 }
16
17 private void button1_Click(object sender, EventArgs e) //输入的数
18 {
19 //将事件源转换为按钮
20 Button btn = sender as Button;
21 //替换(文本框内容为0，点击了运算符)
22 if (prev == 2 || txtbottom.Text == "0")
23 {
24 txtbottom.Text = btn.Text;
25 }
26 //追加(内容不为0，并且上次没有点击运算符)
27 else
28 {
29 txtbottom.Text += btn.Text;
30 }
31 //点击了按钮数字
32 prev = 1;
33 }
34
35 private void button4_Click(object sender, EventArgs e) //加减乘除
36 {
37 //事件源转换为按钮
38 Button btn = sender as Button;
39 //上次按了数字
40 if (prev == 1)
41 {
42 txttop.Text += txtbottom.Text + btn.Text;//进行显示拼接
43 switch (prevysf)
44 {
45 case "+":
46 zjjg = zjjg + Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
47 break;
48 case "-":
49 zjjg = zjjg - Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
50 break;
51 case "*":
52 zjjg = zjjg * Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
53 break;
54 case "/":
55 zjjg = zjjg / Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
56 break;
57 }
58
59 txtbottom.Text = zjjg.ToString();
60 }
61 //上次按了运算符
62 else
63 {
64
65 if (txttop.Text != "")
66 {
67 string s = txttop.Text;
68 s = s.Substring(0, s.Length - 1);
69 s = s + btn.Text;
70 txttop.Text = s;
71 }
72 else
73 {
74
75 txttop.Text = txtbottom.Text + btn.Text;
76 }
77 }
78 //点击了运算符
79 prev = 2;
80 //记录下运算符
81 prevysf = btn.Text;
82 }
83
84 private void button9_Click(object sender, EventArgs e) //清空
85 {
86 txttop.Text = "";
87 txtbottom.Text = "0";
88 prevysf = "+";
89 prev = 0;
90 zjjg = 0;
91 }
92
93 private void button11_Click(object sender, EventArgs e) //等于
94 {
95 //事件源转换为按钮
96 Button btn = sender as Button;
97 switch (prevysf)
98 {
99 case "+":
100 zjjg = zjjg + Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
101 break;
102 case "-":
103 zjjg = zjjg - Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
104 break;
105 case "*":
106 zjjg = zjjg * Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
107 break;
108 case "/":
109 zjjg = zjjg / Convert.ToDecimal(txtbottom.Text); //计算上次运行的结果
110 break;
111 }
112 txtbottom.Text = zjjg.ToString();
113 txttop.Text = "";
114 prevysf = "";
115 prev = 2;
116 }
117
118 private void button17_Click(object sender, EventArgs e) //回退一个
119 {
120 string s = txtbottom.Text;
121 if (s.Length >1)
122 {
123 s = s.Substring(0, s.Length - 1);
124 txtbottom.Text = s;
125 }
126 else if(s.Length==1)
127 {
128 txtbottom.Text = "0";
129 }
130 }
131
132 private void Form1_Load(object sender, EventArgs e)
133 {
134
135 }
136 }
137 }
