C# 计算器 入门示例代码下载

【实例截图】

【核心代码】

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

namespace Calc
{
    public partial class Form1 : Form
    {
        double temp1 = -1;    //记录第一个数字
        int pos = 0;    //存储计算方式
        public Form1()
        {
            InitializeComponent();
        }

        public void addNum(int num)
        {
            textBox1.Text = textBox1.Text   num.ToString();    //在显示屏中添加数字
        }
        private void groupBox1_Enter(object sender, EventArgs e)
        {

        }

        public void checkTextbox()    //检查显示框是否为空
        {
            if (textBox1.Text == "0")
            {
                textBox1.Clear();
            }
        }

        //按钮1
        private void button1_Click(object sender, EventArgs e)
        {
            checkTextbox();    //调用自定义方法，检查显示框是否为空
            addNum(1);      
        }
        //按钮2
        private void button2_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(2);  
        }
        //按钮3
        private void button3_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(3);
        }
        //按钮4
        private void button4_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(4);
        }
        //按钮5
        private void button5_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(5);
        }
        //按钮6
        private void button6_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(6);
        }
        //按钮7
        private void button7_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(7);
        }
        //按钮8
        private void button8_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(8);
        }
        //按钮9
        private void button9_Click(object sender, EventArgs e)
        {
            checkTextbox();
            addNum(9);
        }
        //按钮0
        private void button10_Click(object sender, EventArgs e)
        {
            addNum(0);
        }

        //除法操作
        private void button15_Click(object sender, EventArgs e)
        {
            pos = 4;
            temp1 = Convert.ToDouble(textBox1.Text);
            textBox1.Text = "";
        }
        //乘法操作
        private void button14_Click(object sender, EventArgs e)
        {
            pos = 3;
            temp1 = Convert.ToDouble(textBox1.Text);
            textBox1.Text = "";
        }
        //减法操作
        private void button13_Click(object sender, EventArgs e)
        {
            pos = 2;
            temp1 = Convert.ToDouble(textBox1.Text);
            textBox1.Text = "";
        }
        //加法操作
        private void button12_Click(object sender, EventArgs e)
        {
            pos = 1;
            temp1 = Convert.ToDouble(textBox1.Text);
            textBox1.Text = "";
        }
        //Result(=)
        private void button17_Click(object sender, EventArgs e)
        {
            operating Op = new operating();
            double temp2 = Convert.ToDouble(textBox1.Text);
            switch (pos)
            {
                case 1:
                    textBox1.Text = Op.add(temp1, temp2);
                    break;
                case 2:
                    textBox1.Text = Op.sub(temp1, temp2);
                    break;
                case 3:
                    textBox1.Text = Op.mul(temp1, temp2);
                    break;
                case 4:
                    textBox1.Text = Op.div(temp1, temp2);
                    break;
            }
        }
        //归零操作
        private void button16_Click(object sender, EventArgs e)
        {
            textBox1.Text = "0";
            temp1 = 0;
            pos = 0;
        }
        //添加小数点的代码
        private void button11_Click(object sender, EventArgs e)
        {
            if (textBox1.Text == "")
            {
                textBox1.Text = "0.";
            }
            else if (textBox1.Text.IndexOf(".") >= 0)
            {
                MessageBox.Show("已经添加了小数点！", "提示");
            }
            else
            {
                textBox1.Text = textBox1.Text   ".";
            }
        }

    }
}