简易四则运算

说明：
在做完每道题后要按'Enter'键提交。如果自己选择用哪种计算类型，每次计算都要选择。随机运算也是每次计算都要选择一次。

Form1的代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace 四则运算
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        public static int count = 0;//题目总数
        private int t = 60;         //测试时间为60秒
        public static int right = 0;//正确的题目总数
        public int sum;
        //产生 0-10 的随机数并显示在文本框中
        private void RandomNum()
        {
            Random ran = new Random();
            int n1, n2;
            n1 = ran.Next(0, 11);
            n2 = ran.Next(0, 11);
            textBox1.Text = Convert.ToString(n1);
            textBox3.Text = Convert.ToString(n2);
            textBox4.Text = "";
            count++;
        }
        //产生四则运算的随机符号并显示在文本框中
        private void RandomSun()
        {
            char[] chars=new char[]{'+','-','*','/'};
            Random ran = new Random();
            char n3;
            n3=chars[ran.Next(0,chars.Length)];
            textBox2.Text = Convert.ToString(n3);
        }
        //加法运算
        private void button1_Click(object sender, EventArgs e)
        {
            textBox4.Focus();
            RandomNum();
            sum = int.Parse(textBox1.Text) + int.Parse(textBox3.Text);
        }
        //减法运算
        private void button2_Click(object sender, EventArgs e)
        {
            textBox4.Focus();
            RandomNum();
            if (int.Parse(textBox1.Text) < int.Parse(textBox3.Text))//处理结果为负数的情况
            {
                sum = int.Parse(textBox3.Text) - int.Parse(textBox1.Text);
            }
            else
            {
                sum = int.Parse(textBox1.Text) - int.Parse(textBox3.Text);
            }
        }
        //乘法运算
        private void button3_Click(object sender, EventArgs e)
        {
            textBox4.Focus();
            RandomNum();
            sum = int.Parse(textBox1.Text) * int.Parse(textBox3.Text);
        }
        //除法运算
        private void button4_Click(object sender, EventArgs e)
        {
            textBox4.Focus();
            RandomNum();
            if (int.Parse(textBox3.Text) != 0)//处理分母为零的情况
            {
                sum =int.Parse(textBox1.Text) / int.Parse(textBox3.Text);
            }
            else
            {                
                RandomNum();
                count=count - 1;
            }
        }
        //开始的单击事件
        private void button6_Click(object sender, EventArgs e)
        {
            label2.Text = t.ToString();
            timer1.Enabled = true;
            timer1.Interval = 1000;
            timer1.Start();
            textBox4.Focus();
        }
        private void timer1_Tick(object sender, EventArgs e)
        {
            if (t <= 0)
            {
                timer1.Enabled = false;
                textBox4.Enabled = false;
                MessageBox.Show("时间！到!");
                textBox4.Enabled = false;
                Form2 frm = new Form2();
                frm.ShowDialog();
            }
            t = t - 1;
            label2.Text = t.ToString();
        }

        private void textBox4_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                    if (textBox4.Text == sum.ToString())
                        right++;
            }
        }
        //停止的单击事件
        private void button7_Click(object sender, EventArgs e)
        {
            timer1.Enabled = false;
            textBox4.Enabled = false;
            Form2 frm = new Form2();
            frm.ShowDialog();
        }
        //随机算法的单击事件
        private void button5_Click(object sender, EventArgs e)
        {
            RandomSun();
            RandomNum();
            textBox4.Focus();
            string str = textBox2.Text.ToString();
            switch (str)
            {
                case "+":
                    sum = Convert.ToInt32(textBox1.Text) + Convert.ToInt32(textBox3.Text);
                    break;
                case "-":
                    if (int.Parse(textBox1.Text) < int.Parse(textBox3.Text))//处理结果为负数的情况
                    {
                        sum = Convert.ToInt32(textBox3.Text) - Convert.ToInt32(textBox1.Text);
                    }
                    sum = Convert.ToInt32(textBox1.Text) - Convert.ToInt32(textBox3.Text);
                    break;
                case "*":
                    sum = Convert.ToInt32(textBox1.Text) * Convert.ToInt32(textBox3.Text);
                    break;
                default:
                    if (int.Parse(textBox3.Text) != 0)//处理分母为零的情况
                    {
                        sum = int.Parse(textBox1.Text) / int.Parse(textBox3.Text);
                    }
                    else
                    {
                        RandomNum();
                        count = count - 1;
                    }
                    break;
            }           
        }        
    }
}

Form2的代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace 四则运算
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void Form2_Load(object sender, EventArgs e)
        {
            textBox1.Text = Form1.count.ToString();
            textBox2.Text = Form1.right.ToString();
            textBox3.Text = (Form1.count - Form1.right).ToString();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }
    }
}

　总结：

做完这个程序，我发现有很多地方都可以再进一步简化，但是我不知道该怎么改，发现原来在这门语言上我才学习那么一点知识啊，是该多看看关于这方面的书了！

Psp分析

PSP	Pensonal	Time
Planning	计划	30（m）
Estimate	估计这个任务需要的时间是	2（h）
Development	开发	3（h)
Analysis	需求分析	20(m)
Design  Review	设计复审	30(m)
Design	具体设计	20(m)
Coding	具体编码	2(h)
Code Review	代码复审	10(m)
Test	测试	10(m)