四则运算的程序

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以上是第二张图片



以上是第三张图片



以上是第四张图片



以上是第五张图片



以上是最后的图片。

做题思路：先建立了基本的框架，然后把计时器做好，再然后定义随机数和单击事件和让用户选择运算法，并让结果以窗口显示，最后检查程序。

这次代码用到了swift语句，共有3个窗体，Form1共有button控件7个，textBox控件3个，label控件4个。Form2主要是统计计算结果的有label控件3个，textBox控件3个。

Form3主要是说明这个程序的用途。计划10h完成，分析用了1h，设计框架0.5h，代码用了4h，检查和写总结用了1h，实际用6.5h。

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 _7._8
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public static int Count = 0;
private int t = 60;
public static int right = 0;
private void button1_Click(object sender, EventArgs e)
{
label4.Text=t.ToString();
timer1.Enabled = true;
timer1.Interval = 1000;
timer1.Start();
RandomNum();
}
private void RandomNum()
{
Random ran = new Random();
int n1, n2;
n1 = ran.Next(1, 11);
n2 = ran.Next(1, 11);
textBox1.Text = n1.ToString();
textBox2.Text = n2.ToString();
textBox3.Text = "";
Count++;
}

private void timer1_Tick(object sender, EventArgs e)
{
if (t <= 0)
{
timer1.Enabled = false;
textBox3.Enabled = false;
MessageBox.Show("时间到！");
textBox3.Enabled = false;
Form2 frm = new Form2();
frm.ShowDialog();
}
t = t - 1;
label4.Text = t.ToString();
}

private void textBox3_KeyDown(object sender, KeyEventArgs e)
{
int text3;
string a = label1.Text;
switch (a)
{
case "+":
text3 = int.Parse(textBox1.Text) + int.Parse(textBox2.Text);
break;
case "-":
text3 = int.Parse(textBox1.Text) - int.Parse(textBox2.Text);
break;
case "*":
text3 = int.Parse(textBox1.Text) * int.Parse(textBox2.Text);
break;
default:
text3 = int.Parse(textBox1.Text) / int.Parse(textBox2.Text);
break;
}

if (e.KeyCode == Keys.Enter)
{
if (textBox3.Text == text3.ToString())
right++;
RandomNum();
}
}

private void button2_Click(object sender, EventArgs e)
{
textBox3.Enabled = false;
Form2 frm2 = new Form2();
frm2.ShowDialog();
}

private void button3_Click(object sender, EventArgs e)
{
new Form3().Show();
}

private void button4_Click(object sender, EventArgs e)
{
label1.Text = "+ ";
}

private void button5_Click(object sender, EventArgs e)
{
label1.Text = "-";
}

private void button6_Click(object sender, EventArgs e)
{
label1.Text = "*";
}

private void button7_Click(object sender, EventArgs e)
{
label1.Text = "/";
}

}
}

　　最后是完整代码