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

namespace Pro67
{
    public partial class Form1 : Form
    {
        int x = 1, op1, op2, op, re1, re2, re3, re4, re5, right = 0, error = 0, score = 0;
        string ss;
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            label1.Text = ct(out re1);//re1...第一个式子的正确结果
            label2.Text = ct(out re2);
            label3.Text = ct(out re3);
            
        }
        public String tj(String  s,int r) {
            if (int.Parse(s) == r)
            {
                right += 1;
                return "正确";

            }
            else {
                error += 1;
                return"错误";
            }
        
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            
        }

        private void 简单ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            x = 1;
        }

        private void 中等ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            x = 2;
        }

        private void 极难ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            x = 3;
        }
        public String ct(out int re) {
            Random rad = new Random();
            op = rad.Next(0, 3) + 1;
            if(x==1){
                op1 = rad.Next(0,9) + 1;
                op2 = rad.Next(0, 9) + 1;

            }
            else if (x == 2)
            {
                Random rnd = new Random();
                op1 = rnd.Next(9, 19) + 1;
                op2 = rnd.Next(9, 19) + 1;
                op = rnd.Next(0, 3) + 1;  //[1,4]
            }
            else {
                Random rnd = new Random();
                op1 = rnd.Next(19, 29) + 1;      
                op2 = rnd.Next(19, 29) + 1;
                op = rnd.Next(0, 3) + 1;   
            }
            switch (op)
            {
                case 1: re = op1 + op2;
                    ss = op1.ToString() + "+" + op2.ToString() + "="; break;
                case 2: re = op1 - op2;
                    ss = op1.ToString() + "-" + op2.ToString() + "="; break;
                case 3: re = op1 * op2;
                    ss = op1.ToString() + "*" + op2.ToString() + "="; break;
                case 4: re = op1 / op2;
                    ss = op1.ToString() + "/" + op2.ToString() + "="; break;
            }
            re = 1;
            return ss;
        }

        private void button2_Click(object sender, EventArgs e)
        {
            label4.Text = tj(textBox1.Text,re1);
            label5.Text = tj(textBox2.Text,re2);
            label6.Text = tj(textBox3.Text,re3);
            richTextBox1.Text += DateTime.Now.Year + "年" + DateTime.Now.Month + "月" + DateTime.Now.Day + "日  ，做的题是："
            + label1.Text + textBox1.Text + label4.Text + "," + label2.Text + textBox2.Text + label5.Text + "," + label3.Text + textBox3.Text + label6.Text + ",成绩" + score;
        }

    }
}
出的题都一样，而且给出正确答案，还是说是错的，怎么回事？

变量re应该就是答案吧，ct最后输出re=1了,应该答案永远都是1...

public String ct(out int re) {
            Random rad = new Random();
            op = rad.Next(0, 3) + 1;
            if(x==1){
                op1 = rad.Next(0,9) + 1;
                op2 = rad.Next(0, 9) + 1;

            }
你这里就判断它是否等于1，而你开始就把x赋值为1，所以应该是只会跳进这个判断里面，就只会在这个里面产生值，还有就是你里面的写的判断乱七八糟的random是个随机产生数类，但是你却把它和switch一起用，我也不知道你想表达的是什么意思！总体来说很乱！

这是要做测试程序么。。。跟我做的毕业设计。。。。好怀念那个时候哦

是课程设计