C#学习使用

今天按照学习C#的计划是要做一个计算机的窗体程序 

可以实现两位数的计算 包括加减乘除 平方开方等

double a = 0;  
  double b = 0; 
  bool c = false; 
  string d; 
(3)双击”1”按钮，添加如下事件处理程序： 
  private void button1_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
           textBox1.Text = ""; 
           c = false; 
      } 
      textBox1.Text += "1"; 
  } 
(4)双击”2”按钮，添加如下事件处理程序： 
  private void button2_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
           textBox2.Text = ""; 
           c = false; 
      } 
           textBox1.Text += "2"; 
  } 
 (5)双击”3”按钮，添加如下事件处理程序： 
  private void button3_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
           textBox3.Text = ""; 
           c = false; 
      } 
      textBox1.Text += "3"; 
  } 
 (6)双击”4”按钮，添加如下事件处理程序： 
  private void button4_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
           textBox1.Text = ""; 
           c = false; 
      } 
      textBox1.Text += "4"; 
  } 
 (7)双击”5”按钮，添加如下事件处理程序： 
  private void button5_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
          textBox1.Text = ""; 
          c = false; 
      } 
      textBox1.Text += "5"; 
  } 
  (8)双击”6”按钮，添加如下事件处理程序： 
  private void button6_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
          textBox1.Text = ""; 
          c = false; 
      } 
      textBox1.Text += "6"; 
  } 
 (8)双击”7”按钮，添加如下事件处理程序： 
  private void button7_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
          textBox1.Text = ""; 
          c = false; 
      } 
      textBox1.Text += "7"; 
  } 
  (10)双击”8”按钮，添加如下事件处理程序： 
  private void button8_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
          textBox1.Text = ""; 
          c = false; 
      } 
      textBox1.Text += "8"; 
  } 
  (11)双击”9”按钮，添加如下事件处理程序： 
  private void button9_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
           textBox1.Text = ""; 
           c = false; 
      } 
      textBox1.Text += "9"; 
  } 
  (12)双击”0”按钮，添加如下事件处理程序： 
  private void button12_Click(object sender, EventArgs e) 
  { 
      if (c == true) 
      { 
          textBox1.Text = ""; 
          c = false; 
      } 
      textBox1.Text += "0"; 
      if (d == "/") 
      { 
          textBox1.Clear(); 
     MessageBox.Show("除数不能为零", "错误提示", MessageBoxButtons.OK, 
MessageBoxIcon.Warning); 
      } 
  } 
  (13)双击”+”按钮，添加如下事件处理程序： 
  private void button13_Click(object sender, EventArgs e) 
  { 
      c = true; 
      b = double.Parse(textBox1.Text); 
      d = "+"; 
  } 
  (14)双击”-”按钮，添加如下事件处理程序： 
  private void button16_Click(object sender, EventArgs e) 
  { 
      c = true; 
      b = double.Parse(textBox1.Text); 
      d = "-"; 
  } 
  (15)双击”*”按钮，添加如下事件处理程序： 
  private void button15_Click(object sender, EventArgs e) 
  { 
      c = true; 
      b = double.Parse(textBox1.Text); 
      d = "*"; 
  } 
  (16)双击”/”按钮，添加如下事件处理程序： 
  private void button14_Click(object sender, EventArgs e) 
  { 
      c = true; 
      b = double.Parse(textBox1.Text); 
      d = "/"; 
  } 
  (17)双击”=”按钮，添加如下事件处理程序： 
  private void button17_Click(object sender, EventArgs e) 
  { 
      switch (d) 
      { 
          case "+": a = b + double.Parse(textBox1.Text); break; 
          case "-": a = b - double.Parse(textBox1.Text); break; 
          case "*": a = b * double.Parse(textBox1.Text); break; 
          case "/": a = b / double.Parse(textBox1.Text); break; 
      } 
      textBox1.Text = a + ""; 
      c = true; 
  } 
(18)双击”c”按钮，添加如下事件处理程序： 
  private void button18_Click(object sender, EventArgs e) 
  { 
      textBox1.Text = ""; 

在计算器中，增加四个功能键：x2，sqrt，log, ln 四个键，分别计算求平方，开方，
log，ln 值，将增加的代码写入实验报告。
 
      private void button20_Click(object sender, EventArgs e)
        {
            //X2
            double a=double.Parse(label1.Text);
            a = a * a;
            label1.Text =""+a;
        }

        private void button19_Click(object sender, EventArgs e)
        {
            double a = double.Parse(label1.Text);
            a = Math.Sqrt(a);
            label1.Text = "" + a;
        }

        private void button18_Click(object sender, EventArgs e)
        {
            double a = double.Parse(label1.Text);
            a = Math.Log(a);
            label1.Text = "" + a;
        }

        private void button17_Click(object sender, EventArgs e)
        {
            double a = double.Parse(label1.Text);
            a = Math.Log10(a);
            label1.Text = "" + a;
        }