求一款C#用windows视窗应用程序制作的计算器

// 计算器源码
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace jisuan
{
 /// 

 /// Form1 的摘要说明。
 /// 

 public class Form1 : System.Windows.Forms.Form
 {
  private System.Windows.Forms.TextBox textBox1;
  private System.Windows.Forms.TextBox textBox2;
  private System.Windows.Forms.TextBox textBox3;
  private System.Windows.Forms.ComboBox comboBox1;
  private System.Windows.Forms.Button button1;
  private System.Windows.Forms.Button button2;
  private System.Windows.Forms.Button button3;
  /// 

  /// 必需的设计器变量。
  /// 

  private System.ComponentModel.Container components = null;

  public Form1()
  {
   //
   // Windows 窗体设计器支持所必需的
   //
   InitializeComponent();

   //
   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
   //
  }

  /// 

  /// 清理所有正在使用的资源。
  /// 

  protected override void Dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null) 
    {
     components.Dispose();
    }
   }
   base.Dispose( disposing );
  }

  #region Windows 窗体设计器生成的代码
  /// 

  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// 

  private void InitializeComponent()
  {
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.textBox3 = new System.Windows.Forms.TextBox();
            this.comboBox1 = new System.Windows.Forms.ComboBox();
            this.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            this.button3 = new System.Windows.Forms.Button();
            this.SuspendLayout();
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(24, 72);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(100, 21);
            this.textBox1.TabIndex = 0;
            this.textBox1.TextChanged += new System.EventHandler(this.textBox1_TextChanged);
            // 
            // textBox2
            // 
            this.textBox2.Location = new System.Drawing.Point(312, 72);
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(100, 21);
            this.textBox2.TabIndex = 1;
            // 
            // textBox3
            // 
            this.textBox3.Location = new System.Drawing.Point(448, 72);
            this.textBox3.Name = "textBox3";
            this.textBox3.Size = new System.Drawing.Size(88, 21);
            this.textBox3.TabIndex = 2;
            // 
            // comboBox1
            // 
            this.comboBox1.Items.AddRange(new object[] {
            "+",
            "-",
            "*",
            "/"});
            this.comboBox1.Location = new System.Drawing.Point(152, 72);
            this.comboBox1.Name = "comboBox1";
            this.comboBox1.Size = new System.Drawing.Size(121, 20);
            this.comboBox1.TabIndex = 3;
            this.comboBox1.SelectedIndexChanged += new System.EventHandler(this.comboBox1_SelectedIndexChanged);
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(64, 184);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(104, 32);
            this.button1.TabIndex = 4;
            this.button1.Text = "计算";
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // button2
            // 
            this.button2.Location = new System.Drawing.Point(216, 192);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(75, 23);
            this.button2.TabIndex = 5;
            this.button2.Text = "清除";
            this.button2.Click += new System.EventHandler(this.button2_Click);
            // 
            // button3
            // 
            this.button3.Location = new System.Drawing.Point(376, 192);
            this.button3.Name = "button3";
            this.button3.Size = new System.Drawing.Size(75, 23);
            this.button3.TabIndex = 6;
            this.button3.Text = "退出";
            this.button3.Click += new System.EventHandler(this.button3_Click);
            // 
            // Form1
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
            this.ClientSize = new System.Drawing.Size(656, 366);
            this.Controls.Add(this.button3);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.comboBox1);
            this.Controls.Add(this.textBox3);
            this.Controls.Add(this.textBox2);
            this.Controls.Add(this.textBox1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);
            this.PerformLayout();

  }
  #endregion

  /// 

  /// 应用程序的主入口点。
  /// 

  [STAThread]
  static void Main() 
  {
   Application.Run(new Form1());
  }
  public double jia(double a,double b)
  {
   return a+b;
  }
  public double jian(double a,double b)
  {
   return a-b;
  }
  public double cheng(double a,double b)
  {
   return a*b;
  }
  public double chu(double a,double b)
  {
   return a/b;
  }

private void comboBox1_SelectedIndexChanged(object sender, System.EventArgs e)
        {

        }

        private void textBox1_TextChanged(object sender, System.EventArgs e)
        {

        }

  private void button1_Click(object sender, System.EventArgs e)
  {
   string i=this.comboBox1.SelectedItem.ToString();

   switch(i)
   {
    
    case "+":this.textBox3.Text=this.jia(double.Parse(this.textBox1.Text),double.Parse(this.textBox2.Text)).ToString();
     
    break;

    case "-":this.textBox3.Text=this.jian(double.Parse(this.textBox1.Text),double.Parse(this.textBox2.Text)).ToString();
    break;
    case "*":this.textBox3.Text=this.cheng(double.Parse(this.textBox1.Text),double.Parse(this.textBox2.Text)).ToString();
    break;
    case"/" :this.textBox3.Text=this.chu(double.Parse(this.textBox1.Text),double.Parse(this.textBox2.Text)).ToString();
    break;
   }

  }

  private void button2_Click(object sender, System.EventArgs e)
  {
   this.textBox1.Text=null;
   this.textBox2.Text=null;
            this.textBox3.Text = null;
  }

        private void button3_Click(object sender, EventArgs e)
        {
            
            //this.Hide();
            Application.Exit();
            //this.Close();
           
        }
 }
}

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