ASP.NET--程序异常处理(实战案例)

案例1：实现在线计算器

步骤：

其代码为；

{

try

{

double a = Convert.ToDouble(TextBox1.Text);

double b = Convert.ToDouble(TextBox2.Text);

if (DropDownList1.SelectedValue == "加")

{

TextBox3.Text = Convert.ToString(a + b);

}

else if (DropDownList1.SelectedValue == "减")

{

TextBox3.Text = Convert.ToString(a - b);

}

else if (DropDownList1.SelectedValue == "乘")

{

TextBox3.Text = Convert.ToString(a * b);

}

else if (DropDownList1.SelectedValue == "除")

{

if (b != 0)

{

TextBox3.Text = Convert.ToString(a / b);

}

else

{

TextBox3.Text = "不能除以0，你不知道？";

}

}

}

catch

{

TextBox3.Text = "请输入数字";

}

}

}

案例2：显示乘法口诀

步骤：

其代码为；

数字型：

{
        int sum = 0;
        for (int i = 1; i <= 9; i++)
        {
            for (int j = 1; j <= i; j++)
            {
               sum = i * j;
                Label1.Text = Label1.Text + j.ToString() + "x" + i.ToString() + "=" + sum.ToString() + "&nbsp;";
            }

            Label1.Text += "</br>";
        }

    }
}

汉字型：

 {
      int sum = 0;
      string s1;
      string s2;
      string[] yezi = { "十", "一", "二", "三", "四", "五", "六", "七", "八", "九" };
      for (int i = 1; i <= 9; i++)
      {
          for (int j = 1; j <= i; j++)
          {
              sum = i * j;
              if (sum < 10)
              {
                  Label1.Text = Label1.Text + yezi[j] + yezi[i] + "得" + yezi[sum] + "　&nbsp;";
              }
              else
              {
                  if (sum % 10 != 0)
                  {
                      s1 = sum.ToString().Substring(0, 1);
                      s2 = sum.ToString().Substring(1, 1);
                      Label1.Text = Label1.Text + yezi[j] + yezi[i] + yezi[Convert.ToInt32(s1)] + "十" + yezi[Convert.ToInt32(s2)] + "&nbsp;";
                  }
                  else
                  {
                      s1 = sum.ToString().Substring(0, 1);
                      s2 = sum.ToString().Substring(1, 1);
                      Label1.Text = Label1.Text + yezi[j] + yezi[i] + yezi[Convert.ToInt32(s1)] + yezi[Convert.ToInt32(s2)] + "　&nbsp;";
                  }
              }
          }
          Label1.Text += "</br>";
      }

    }
}