c# 计算器2.0源码

主要时间浪费在

//执行计算
object result = new DataTable().Compute(s, "");

这条语句上。如果不加处理，特别大的整数相乘，会提示值 太大。只好将整数加个0变为小数；

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

namespace JcCalc
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();
        }

        private void btn0_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "0";
        }

        private void btn1_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "1";
        }

        private void btn2_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "2";
        }

        private void btn3_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "3";
        }

        private void btn4_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "4";
        }

        private void btn5_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "5";
        }

        private void btn6_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "6";
        }

        private void btn7_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "7";
        }

        private void btn8_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "8";
        }

        private void btn9_Click(object sender, EventArgs e)
        {
            rtbResult.Text += "9";
        }
        //加法
        private void btnAdd_Click(object sender, EventArgs e)
        {
            lbResult.Text = "";
            string s = rtbResult.Text;
            //判断输入框是否为空
            if (s.Length > 0)
            {
                s = s.Substring(s.Length - 1);
                //如果最后一个是运算符，则返回不执行操作；
                if ("+-*/.".Contains(s)) return;
                rtbResult.Text += "+";
            }

        }
        //减法
        private void btnSub_Click(object sender, EventArgs e)
        {
            lbResult.Text = "";
            string s = rtbResult.Text;
            //判断输入框是否为空
            if (s.Length > 0)
            {
                s = s.Substring(s.Length - 1);
                //如果最后一个是运算符，则返回不执行操作；
                if ("+-*/.".Contains(s)) return;
                rtbResult.Text += "-";
            }
        }
        //乘法
        private void btnMul_Click(object sender, EventArgs e)
        {
            lbResult.Text = "";
            string s = rtbResult.Text;
            //判断输入框是否为空
            if (s.Length > 0)
            {
                s = s.Substring(s.Length - 1);
                //如果最后一个是运算符，则返回不执行操作；
                if ("+-*/.".Contains(s)) return;
                rtbResult.Text += "*";
            }
        }
        //除法
        private void btnDiv_Click(object sender, EventArgs e)
        {
            lbResult.Text = "";
            string s = rtbResult.Text;
            //判断输入框是否为空
            if (s.Length > 0)
            {
                s = s.Substring(s.Length - 1);
                //如果最后一个是运算符，则返回不执行操作；
                if ("+-*/.".Contains(s)) return;
                rtbResult.Text += "/";
            }
        }

        private void btnClear_Click(object sender, EventArgs e)
        {
            rtbResult.Text = "";
            lbResult.Text = "";
        }

        private void btnDel_Click(object sender, EventArgs e)
        {
            string s = rtbResult.Text;
            //如果S长度大于0，则删除最后一位；
            if (s.Length > 0) s = s.Substring(0, s.Length - 1);
            rtbResult.Text = s;
        }

        private void btnPoint_Click(object sender, EventArgs e)
        {
            string s = rtbResult.Text;
            //判断输入框是否为空
            if (s.Length > 0)
            {
                s = s.Substring(s.Length - 1);
                //如果最后一个是运算符，则返回不执行操作；
                if ("+-*/.".Contains(s)) return;
                rtbResult.Text += ".";
            }
        }

        private void button19_Click(object sender, EventArgs e)
        {
            float dResult = 0;
            string s = rtbResult.Text;
            //判断输入框是否为空
            try
            {
                if (s.Length > 0)
                {
                    //如果没有运算符
                    if (s.IndexOf("+") < 0 && s.IndexOf("-") < 0 && s.IndexOf("*") < 0 && s.IndexOf("/") < 0)
                    {
                        return;
                    }
                    //这是执行“object result = new DataTable().Compute(s, "");”
                    //遇到的一个问题
                    //如果有特别大的整数相乘，会出现错误，需要将其转换为带小数位的数
                    if (s.IndexOf("*") > 0)
                    {
                        string tmpOperate = "";
                        string sTemp = "";
                        string sMul = s.Substring(0, s.IndexOf("*"));
                        //如果没有小数，直接处理后就结束 
                        int tt = sMul.IndexOf(".");
                        if (sMul.IndexOf(".") <= 0)
                        {
                            sTemp = s.Substring(0, s.IndexOf("*"));
                            sTemp += ".0";
                            sTemp += s.Substring(s.IndexOf("*"));
                            s = sTemp;
                        }
                        else
                        {
                            for (int i = sMul.Length; i > 0; i--)
                            {
                                tmpOperate = sMul.Substring(i-1, 1);
                                //如果已经是小数了就结束 
                                if (tmpOperate == ".") return;
                                //如果不是小数，就在整数后面加上 .0使其变为小数，防止计算整数出错；
                                if (tmpOperate == "+" || tmpOperate == "-" || tmpOperate == "*" || tmpOperate == "/")
                                {
                                    sTemp = s.Substring(0, s.IndexOf("*"));
                                    sTemp += ".0";
                                    sTemp += s.Substring(s.IndexOf("*"));
                                    s = sTemp;
                                    break;
                                }
                            }
                        }

                    }
                    //执行计算
                    object result = new DataTable().Compute(s, "");
                    string s2 = result.ToString();
                    if (s2 == "∞")
                    {
                        MessageBox.Show("除数不能为0");
                        return;
                    }
                    lbResult.Text = s2.ToString();
                }
            }
            catch (Exception E)
            {
                MessageBox.Show("我是3年级的小屁孩，数字多了我算不出来！\r\n提示：" + E.Message, "有点小尴尬");
                return;
            }


        }

        /// <summary>
        /// 最简单的方式由SQL计算
        /// </summary>
        /// <param name="expression">表达式</param>
        /// <returns></returns>

        private void btnHelp_Click(object sender, EventArgs e)
        {
            MessageBox.Show("谢谢你长得辣么美，还在点击我！", "三克油");
        }
    }
}