winform 简易计算器

来源：互联网发布：json null值转换成空编辑：程序博客网时间：2024/06/05 21:37

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 winform__计算器
{
    public partial class Form1 : Form
    {
        int i;//声明一个全局变量

        public Form1()
        {
            InitializeComponent();
        }

private void textBox1_TextChanged(object sender, EventArgs e)
{

}

private void Form1_Load(object sender, EventArgs e)
{

}

        private void button1_Click(object sender, EventArgs e)
        {
            //加

                i = 1;

        }

        private void button2_Click(object sender, EventArgs e)
        {
            //减

i = 2;

}

        private void button3_Click(object sender, EventArgs e)
        {
            //乘

                i = 3;
        }

        private void button4_Click(object sender, EventArgs e)
        {
            //除

                i = 4;
        }

        private void button5_Click(object sender, EventArgs e)
        {
            double num1, num2, result = 0;//声明三个变量，二个是用来计算的，一个是结果
            num1 = double.Parse(t1.Text);//获取第一个对话框的值并转换成double类型
            num2 = double.Parse(t2.Text);//获取第二个对话框的值并转换成double类型

            switch (i)//通过i来判断该执行的运算
            {
                case 1: result = num1 + num2; break;
                case 2: result = num1 - num2; break;
                case 3: result = num1 * num2; break;
                case 4: result = num1 / num2; break;
                default: MessageBox.Show("请选择要执行的运算"); break;
            }

t3.Text = Convert.ToString(result);//把结果显示在第三个对话框里

i = 0;//把i设回为0

}
}
}