C#动态生成简便计算器

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 计算器
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }
        Point p;
        Point pp;
        private void Form2_Load(object sender, EventArgs e)
        {
            Button btn;
            Label lbl = new Label();
            lbl.Name = "lblname";
            lbl.Location = new Point(50,10);//定位置
            lbl.Size = new Size(250,30);//定尺寸
            TextBox txt = new TextBox();
            txt.Name = "txtName";
            txt.BorderStyle = BorderStyle.FixedSingle;//设置样式
            txt.Location = new Point(50,30);
            txt.Size = new Size(250,50);
            txt.Multiline = true;//设置为多行文本框
            Button btn0 = new Button();
            btn0.SetBounds(p.X+50,p.Y+230,150,50);//设置位置和尺寸
            btn0.Tag = 0;
            btn0.Visible = true;
            btn0.Text = 0 + "";
            btn0.Click += new EventHandler(btn_Click);//手动添加事件
            Button btnJ = new Button();
            btnJ.SetBounds(p.X+200,p.Y+80,50,50);
            btnJ.Tag = "+";
            btnJ.Text = "+";
            btnJ.Click += new EventHandler(btn_Click);
            Button btnJan = new Button();
            btnJan.SetBounds(p.X + 200, p.Y + 130, 50, 50);
            btnJan.Tag = "-";
            btnJan.Text = "-";
            btnJan.Click += new EventHandler(btn_Click);
            Button btnC = new Button();
            btnC.SetBounds(p.X + 200, p.Y + 180, 50, 50);
            btnC.Tag = "*";
            btnC.Text = "*";
            btnC.Click += new EventHandler(btn_Click);
            Button btnChu = new Button();
            btnChu.SetBounds(p.X + 200, p.Y + 230, 50, 50);
            btnChu.Tag = "/";
            btnChu.Text = "/";
            btnChu.Click += new EventHandler(btn_Click);
            Button btnQ = new Button();
            btnQ.SetBounds(p.X + 250, p.Y + 80, 50, 50);
            btnQ.Tag = "C";
            btnQ.Text = "C";
            btnQ.Click += new EventHandler(btn_Click);
            Button btnD = new Button();
            btnD.SetBounds(p.X + 250, p.Y + 130, 50, 150);
            btnD.Tag = "=";
            btnD.Text = "=";
            btnD.Click += new EventHandler(btn_Click);
            for (int i = 1; i <=9; i++)
            {
                btn = new Button();
                btn.SetBounds(p.X+50, p.Y+80, 50, 50);
                btn.Text = i+"";
                btn.Tag = i ;
                btn.Visible = true;
                btn.Click += new EventHandler(btn_Click);
                this.Controls.Add(btn);
                p.X += 50;
                if (p.X >= 150)//如果横向尺寸大于150，那么就换行（3个按钮刚好150尺寸）
                {
                    p.X = 0;
                    p.Y += 50;//纵向移动
                }
            }
            this.Controls.Add(txt);//在面板中添加文本框
            this.Controls.Add(btn0);//添加按钮0
            this.Controls.Add(btnJ);//添加+加号按钮
            this.Controls.Add(btnJan);//添加-减号按钮
            this.Controls.Add(btnC);//添加*乘法按钮
            this.Controls.Add(btnChu);//添加/除法按钮
            this.Controls.Add(btnQ);//添加C清空按钮
            this.Controls.Add(btnD);//添加=号按钮
            this.Controls.Add(lbl);//添加lable
        }
        private void btn_Click(object sender, EventArgs e)
        {
           
            Button btn = (Button)sender;
            /*linq写法*/
            string str = this.Controls.OfType<TextBox>().Single(item => item.Name == "txtName").Text;
            string str1 = this.Controls.OfType<Label>().Single(item => item.Name == "lblname").Text;
            /*一般的写法*/
            TextBox txt = this.Controls.Find("txtName", true)[0] as TextBox;
            Label lbl = this.Controls.Find("lblname", true)[0] as Label;
            str1+=btn.Tag.ToString();
            lbl.Text = str1;
            if (str1.IndexOf('=') != -1)//如果字符里面有=号
            {
                str1 = str1.Substring(0,str1.Length-1);//把=号截取掉

                if (str1.IndexOf('+') != -1)//如果剩下的字符串里面有+号
                {
                    string[] nums = str1.Split('+');//把+号的前后字符串分割并装到数组
                    int sum = 0;
                    foreach (var num in nums)//循环遍历数组
                    {
                        sum += Convert.ToInt32(num);
                    }
                    txt.Text = sum.ToString();//文本框获得结果
                    lbl.Text = "";//清空lable里的内容
                }
                 if (str1.IndexOf('-') != -1)
                {
                    string[] nums = str1.Split('-');
                    int subtr = 0;
                    foreach (var num in nums)
                    {
                        subtr -= Convert.ToInt32(num);
                    }
                    txt.Text = subtr.ToString();
                    lbl.Text = "";
                }
                if (str1.IndexOf('*') != -1)
                {
                    string[] nums = str1.Split('*');
                    int mult = 1;
                    foreach (var num in nums)
                    {
                        mult *= Convert.ToInt32(num);
                    }
                    txt.Text = mult.ToString();
                    lbl.Text = "";
                }
                if (str1.IndexOf('/') != -1)
                {
                    string[] nums = str1.Split('/');
                    int division = 1;
                    for (int i = 0; i < nums.Length-1; i++)
                    { 
                        division= Convert.ToInt32(nums[i])/Convert.ToInt32(nums[nums.Length-1]);
                    }
                        //foreach (var num in nums)
                        //{
                        //     division /= Convert.ToInt32(num);
                        //}
                        txt.Text = division.ToString();
                    lbl.Text = "";
                }
            }
            if (str1.IndexOf('C') != -1)
            {
                lbl.Text = "";
                txt.Text = "";
            }
           
          


          // MessageBox.Show(str);
        }
    }
}