设计如下:

代码:
using System;
using System.IO;
public partial class 四则运算 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
public static int right = 0;
protected void Button1_Click(object sender, EventArgs e)
{
int n1 = int.Parse(TextBox1.Text .Trim ());
int n2 = int.Parse(TextBox3 .Text .Trim ());
Char y = Convert.ToChar(TextBox2 .Text .Trim ());
fengzhuang con = new fengzhuang ();
con.cl(n1, n2, y);
if (con.result == int.Parse(TextBox4 .Text .Trim ()))
{
Response.Write("<script>alert(‘回答正确!‘)</script>");
right++;
}
else
{
Response.Write("<script>alert(‘回答错误!‘)</script>");
}
}
protected void Button2_Click(object sender, EventArgs e)
{
ListBox2.Items.Add(TextBox1.Text + TextBox2.Text + TextBox3.Text + Label1 .Text +TextBox4 .Text);
TextBox1.Text="";
TextBox2.Text = "";
TextBox3.Text = "";
TextBox4.Text = "";
}
}

封装类:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
/// <summary>
///fengzhuang 的摘要说明
/// </summary>
public class fengzhuang
{
//
//TODO: 在此处添加构造函数逻辑
//
public char ysf;
public int result = 0;
public void cl(int number1, int number2, char ysf)
{
if(ysf==‘+‘)
{
result=number1+number2;
}
if (ysf == ‘-‘)
{
result=number1-number2;
}
if (ysf== ‘*‘)
{
result=number1*number2;
}
if (ysf == ‘/‘)
{
result=number1/number2;
}
}
}
测试:



原文:http://www.cnblogs.com/64gong/p/5004891.html