ASP.NET创建随机数实现加减乘除（C#版）

效果图：


多个按钮事件绑定为一个名字

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Default4 : System.Web.UI.Page
{
    static float Num1, Num2, Result = 0;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack) {
            Random r = new Random();
            Num1 = r.Next(0, 99);
            Num2 = r.Next(0, 99);
            txtNum1.Text = Num1.ToString();
            txtNum2.Text = Num2.ToString();
        }       
    }
    protected void btn_Click(object sender, EventArgs e)
    {
        Button btn = (Button)sender;
        
        //Num1 = float.Parse(txtNum1.Text);
        //Num2 = float.Parse(txtNum2.Text);       

        switch (btn.ID)
        {
            case "btnAdd":
                Result = Num1 + Num2;
                break;
            case "btnSub":
                Result = Num1 - Num2;
                break;
            case "btnMul":
                Result = Num1 * Num2;
                break;
            case "btnDivi":
                if (int.Parse(txtNum2.Text) == 0)
                {
                    txtResult.Text = "除0错误！";
                }
                else {

                    Result = Num1 / Num2;              
                }
                break;
        }
        txtResult.Text = Result.ToString();
        this.Response.Write(string.Format("{0} {1} {2} = {3}<br/>", txtNum1.Text, btn.ID, txtNum2.Text, txtResult.Text));
    }
    protected void btnConfirm(object sender, EventArgs e)
    {
        Random r = new Random();
        Num1 = r.Next(0, 99);
        Num2 = r.Next(0, 99);
        txtNum1.Text = Num1.ToString();
        txtNum2.Text = Num2.ToString();
    }
}