C＃计算器应用程序

Question

这是我一直试图制作的计算器代码。 我有它的工作，除了我有一个错误，我似乎无法弄清楚如何解决它。

每当用户单击错误的操作员，然后单击他们希望使用的正确操作员时（+按钮-按钮ect）都不会更改为正确的操作员，并且执行的功能将不正确。

    double value_1 = 0;
    bool double_operation = false;
    bool clickable_decimal = true;
    bool operation_pressed = false;
    bool second_click = false;
    bool second_equals = false;
    String math_operator = "";


    private void btn_Click(object sender, EventArgs e)
    {
        if (second_equals == true)
        {
            txt_display.Text = "0";
            //value_1 = 0;
            second_equals = false;
        }
        if ((txt_display.Text == "0") || (operation_pressed == true))
        {
            txt_display.Clear();
        }
        operation_pressed = false;
        Button btn = (Button)sender;
        txt_display.Text = txt_display.Text + btn.Text;
        double_operation = false;

    }

    private void btn_clear_Click(object sender, EventArgs e)
    {
        txt_display.Text = "0";
        value_1 = 0;
    }

    private void btn_deci_Click(object sender, EventArgs e)
    {
        {
            if (clickable_decimal == true)
            {
                Button btn = (Button)sender;
                txt_display.Text = txt_display.Text + btn.Text;
                clickable_decimal = false;
            }

        }
    }

    private void btn_operator_Click(object sender, EventArgs e)
    {
        if (double_operation == false)
        {
            if (second_click == false)
            {

                Button btn = (Button)sender;
                math_operator = btn.Text;
                value_1 = double.Parse(txt_display.Text);
                operation_pressed = true;
                clickable_decimal = true;
                second_equals = false;
            }

            if (second_click == true)
            {
                Button btn = (Button)sender;

                //value_2 = double.Parse(txt_display.Text);
                operation_pressed = true;
                clickable_decimal = true;

                switch (math_operator)
                {
                    case "+":
                        txt_display.Text = (value_1 + double.Parse(txt_display.Text)).ToString();
                        break;

                    case "-":
                        txt_display.Text = (value_1 - double.Parse(txt_display.Text)).ToString();
                        break;

                    case "/":
                        txt_display.Text = (value_1 / double.Parse(txt_display.Text)).ToString();
                        break;

                    case "*":
                        txt_display.Text = (value_1 * double.Parse(txt_display.Text)).ToString();
                        break;

                }//end switch
                value_1 = double.Parse(txt_display.Text);
                math_operator = btn.Text;
                second_equals = true;
            }
            second_click = true;
        }
        double_operation = true;

}

    private void btn_equals_Click(object sender, EventArgs e)
    {
        if (second_equals == false)
        {
            switch (math_operator)
            {
                case "+":
                    txt_display.Text = (value_1 + double.Parse(txt_display.Text)).ToString();
                    break;

                case "-":
                    txt_display.Text = (value_1 - double.Parse(txt_display.Text)).ToString();
                    break;

                case "/":
                    txt_display.Text = (value_1 / double.Parse(txt_display.Text)).ToString();
                    break;

                case "*":
                    txt_display.Text = (value_1 * double.Parse(txt_display.Text)).ToString();
                    break;

            }//end switch
            value_1 = double.Parse(txt_display.Text);
            second_click = false;
            second_equals = true;
        }

Answer 1

您正在使用math_operator存储选定的数学运算符。 仅当second_click == false时才设置其值（在btn_operator_Click() ），因此似乎很清楚为什么第二次单击不改变任何东西。

Answer 2

我想出了答案，任何对此感兴趣的人都是。

    double value_1 = 0;
    bool double_operation = false;
    bool clickable_decimal = true;
    bool operation_pressed = false;
    bool second_click = false;
    bool second_equals = false;
    String math_operator = "";


    private void btn_Click(object sender, EventArgs e)
    {
        if (second_equals == true)
        {
            txt_display.Text = "0";
            //value_1 = 0;
            second_equals = false;
        }
        if ((txt_display.Text == "0") || (operation_pressed == true))
        {
            txt_display.Clear();
        }
        operation_pressed = false;
        Button btn = (Button)sender;
        txt_display.Text = txt_display.Text + btn.Text;
        double_operation = false;

    }

    private void btn_clear_Click(object sender, EventArgs e)
    {
        txt_display.Text = "0";
        value_1 = 0;
    }

    private void btn_deci_Click(object sender, EventArgs e)
    {
        {
            if (clickable_decimal == true)
            {
                Button btn = (Button)sender;
                txt_display.Text = txt_display.Text + btn.Text;
                clickable_decimal = false;
            }

        }
    }

    private void btn_operator_Click(object sender, EventArgs e)
    {
//==========================================================================
        if (double_operation == true)
        {
            math_operator = "";
            double_operation = false;
            second_click = false; // however it will work without this but i       
            //do not know why so ill leave it in 
        }
 // this is the solution 
 //=========================================================================
        if (double_operation == false)
        {
            if (second_click == false)
            {

                Button btn = (Button)sender;
                math_operator = btn.Text;
                value_1 = double.Parse(txt_display.Text);
                operation_pressed = true;
                clickable_decimal = true;
                second_equals = false;
            }

            if (second_click == true)
            {
                Button btn = (Button)sender;
                operation_pressed = true;
                clickable_decimal = true;
                switch (math_operator)
                {
                    case "+":
                        txt_display.Text = (value_1 + double.Parse(txt_display.Text)).ToString();
                        break;

                    case "-":
                        txt_display.Text = (value_1 - double.Parse(txt_display.Text)).ToString();
                        break;

                    case "/":
                        txt_display.Text = (value_1 / double.Parse(txt_display.Text)).ToString();
                        break;

                    case "*":
                        txt_display.Text = (value_1 * double.Parse(txt_display.Text)).ToString();
                        break;

                }//end switch
                value_1 = double.Parse(txt_display.Text);
                math_operator = btn.Text;
                second_equals = true;
            }
            second_click = true;
        }
        double_operation = true;

}

    private void btn_equals_Click(object sender, EventArgs e)
    {
        if (second_equals == false)
        {
            switch (math_operator)
            {
                case "+":
                    txt_display.Text = (value_1 + double.Parse(txt_display.Text)).ToString();
                    break;

                case "-":
                    txt_display.Text = (value_1 - double.Parse(txt_display.Text)).ToString();
                    break;

                case "/":
                    txt_display.Text = (value_1 / double.Parse(txt_display.Text)).ToString();
                    break;

                case "*":
                    txt_display.Text = (value_1 * double.Parse(txt_display.Text)).ToString();
                    break;

            }//end switch
            value_1 = double.Parse(txt_display.Text);
            second_click = false;
            second_equals = true;
        }

通过单击错误的运算符，它将把math_operator重置为math_operator等于任何值，然后将double_operation设置为false，以便其余的（如果下面的代码可以在用户点击正确的运算符时执行）而得以执行。