一、具体代码

类代码

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;

namespace szys
{
    class Class2
    {
        public int Sum;

        public int Answer
        {
            get { return Sum; }

        }
        public int Max(int n1,int n2,char yunsuanfu)
        {
            if (yunsuanfu == ‘+‘)
            {
                return Sum = n1 + n2;
            }
            else if (yunsuanfu == ‘-‘)
            {
                if (n1 > n2)
                {
                    return Sum = n1 - n2;
                }
                else
                {
                    MessageBox.Show("第一个数要大于第二个数！");

                }
            }
            else if (yunsuanfu == ‘/‘)
            {
                if (n2 == 0 || n2 < 0)
                {
                    MessageBox.Show("分母不能为0且大于0！");
                }
                else
                {
                    return Sum = n1 / n2;
                }
            }
            else if (yunsuanfu == ‘*‘)
            {
                return Sum = n1 * n2;

            }
            return Sum;

        }

    }
    }

Form1代码

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

namespace szys
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        public static int right = 0;
        public static int Count = 0;
        private int t;

        private void button5_Click(object sender, EventArgs e)
        {

            string strCon = @"Data Source=.;Initial Catalog=jisuanqi;Integrated Security=True";
            SqlConnection sqlcon = new SqlConnection(strCon);
            try
            {
                sqlcon.Open();
                string slt = @"insert into jisuan(Number1,Operator,Number2)" + " values(‘" + textBox1.Text + "‘,‘" + textBox4.Text + "‘,‘" + textBox2.Text + "‘)";
                SqlCommand cmd = new SqlCommand(slt, sqlcon);
                cmd.ExecuteNonQuery();
                MessageBox.Show("出题成功！");
            }
            catch (Exception ex)
            {
                MessageBox.Show("出题失败"+ex.ToString());
            }
            sqlcon.Close();

            textBox1.Clear();
            textBox4.Clear();
            textBox2.Clear();

        }

        private void button2_Click(object sender, EventArgs e)
        {

            textBox1.Enabled = false;
            textBox2.Enabled = false;
            textBox4.Enabled = false;
            textBox1.BackColor = Color.Yellow;
            textBox4.BackColor = Color.Yellow;
            textBox2.BackColor = Color.Yellow;
            textBox3.BackColor = Color.Yellow;
            string strCon = @"Data Source=.;Initial Catalog=jisuanqi;Integrated Security=True";
            SqlConnection sqlcon = new SqlConnection(strCon);
            int i = 1;
            sqlcon.Open();
            string slt = @"select * from jisuan";
            SqlCommand cmd = new SqlCommand(slt, sqlcon);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            DataTable dt = ds.Tables[0];
            textBox1.Text = dt.Rows[i][0].ToString();
            textBox4.Text = dt.Rows[i][1].ToString();
            textBox2.Text = dt.Rows[i][2].ToString();
            sqlcon.Close();

        }

        private void textBox3_MouseClick(object sender, MouseEventArgs e)//计时;
        {
            label3.Text = t.ToString();
            timer1.Enabled = true;
            timer1.Interval = 1000;
            timer1.Start();
        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            t = t + 1;
            label3.Text = t.ToString();
        }

        private void button3_Click(object sender, EventArgs e)
        {
            MessageBox.Show("一共用时" + label3.Text + "秒");
            Form2 frm2 = new Form2();
            frm2.ShowDialog();
        }

        private void button4_Click(object sender, EventArgs e)
        {
            int a = int.Parse(textBox1.Text);
            int b = int.Parse(textBox2.Text);
            Char c = Convert.ToChar(textBox4.Text.Trim());
            Class2 con = new Class2();
            con.Max(a, b, c);
            if (con.Answer == int.Parse(textBox3.Text))
            {
                MessageBox.Show("恭喜你，小朋友！回答正确！");
                right++;
                Count++;
            }

            else
            {

                MessageBox.Show("回答错误，继续加油！小朋友");
                Count++;

            }
            textBox1.Clear();
            textBox2.Clear();
            textBox3.Clear();
            textBox4.Clear();

        }

    }
}

Form2代码

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

namespace szys
{
    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();
            textBox4.Text = ((Form1.right / (double)(Form1.Count)) * 100).ToString() + "%";

        }

     }
 }

二、测试

三、总结

         用数据库对已出算式题的保存打开就是对数据库的增加查询，首先建一个表，列名有第一个数，运算符，第二个数，然后编写增加查询语句。