C# 让我的计算器在按下“相等”按钮后获取新数字

所以我已经做了一段时间了，仍然不能让我的计算器做最后一件事

我知道了，谢谢

在我按下equal按钮或Tan、Sin、Cos或Mod按钮后，我希望我的计算器获得一个新的数字。基本上就像文本框中什么都没有一样，即使答案仍然存在。目前，所有号码都保留，新号码添加到末尾。我不希望这种情况发生

在计算之后，如果我按下一个数字按钮，我希望它清除屏幕并添加新的数字。下面是我到目前为止的代码

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";

    private void AddButton_Click(object sender, EventArgs e)
    {
        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        mathOperator = "+";

        DisplayTextBox.Text = "";
        DisplayTextBox.Focus();

    }
    private void EqualButton_Click(object sender, EventArgs e)
    {
        Double SecondNumber;
        SecondNumber = Convert.ToDouble(DisplayTextBox.Text);

        switch (mathOperator)
        {
            case "+":
                DisplayTextBox.Text = (FirstNumber + SecondNumber).ToString();
                break;
            case "-":
                DisplayTextBox.Text = (FirstNumber - SecondNumber).ToString();
                break;
            case "*":
                DisplayTextBox.Text = (FirstNumber * SecondNumber).ToString();
                break;
            case "/":
                DisplayTextBox.Text = (FirstNumber / SecondNumber).ToString();
                break;
            default:
                break;
        }
    }

    private void button12_Click(object sender, EventArgs e)
    {
        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        FirstNumber *= -1;
        DisplayTextBox.Text = FirstNumber.ToString();

    }

    private void ButtonMinus_Click(object sender, EventArgs e)
    {

        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        mathOperator = "-";

        DisplayTextBox.Text = "";
        DisplayTextBox.Focus();

    }

    private void ButtonMultiply_Click(object sender, EventArgs e)
    {

        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        mathOperator = "*";

        DisplayTextBox.Text = "";
        DisplayTextBox.Focus();

    }

    private void ButtonDivide_Click(object sender, EventArgs e)
    {

        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        mathOperator = "/";

        DisplayTextBox.Text = "";
        DisplayTextBox.Focus();

    }

    private void ButtonMod_Click(object sender, EventArgs e)
    {
        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        DisplayTextBox.Text = Math.Tan(FirstNumber).ToString();

    }

    private void Button1_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    private void Button2_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "2";
    }

    private void Button3_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "3";
    }

    private void Button4_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "4";
    }

    private void Button5_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "5";
    }

    private void Button6_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "6";
    }

    private void Button7_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "7";
    }

    private void Button8_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "8";
    }

    private void Button9_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = DisplayTextBox.Text + "9";
    }

    private void ButtonClear_Click(object sender, EventArgs e)
    {
        DisplayTextBox.Text = "";
        mathOperator = "";
    }

    private void ButtonOff_Click(object sender, EventArgs e)
    {
        Application.Exit();
    }

    private void ButtonTan_Click(object sender, EventArgs e)
    {
        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        DisplayTextBox.Text = Math.Tan(FirstNumber).ToString();
    }

    private void ButtonSin_Click(object sender, EventArgs e)
    {
        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        DisplayTextBox.Text = Math.Sin(FirstNumber).ToString();

    }

    private void ButtonCos_Click(object sender, EventArgs e)
    {
        FirstNumber = Convert.ToDouble(DisplayTextBox.Text);
        DisplayTextBox.Text = Math.Cos(FirstNumber).ToString();

    }

    private void Button0_Click(object sender, EventArgs e)
    {
        if (DisplayTextBox.Text.Length >= 1)
        {
            DisplayTextBox.Text = DisplayTextBox.Text + "0";
        }
        else
        {
            return;
        }
    }

    private void DecimalButton_Click(object sender, EventArgs e)
    {
        if (DisplayTextBox.Text.Contains("."))
        {
            return;
        }
        else
        {
            DisplayTextBox.Text = DisplayTextBox.Text + ".";
        }
    }
}

---

将状态变量添加到类中。如果为true，并且选择了一个数字，则在写入数字之前清除显示并将其设置为false

---

单击“=”时，将其设置为true。

将状态变量添加到类中。如果为true，并且选择了一个数字，则在写入数字之前清除显示并将其设置为false

---

单击“=”时，将其设置为true。

将状态变量添加到类中。如果为true，并且选择了一个数字，则在写入数字之前清除显示并将其设置为false

---

单击“=”时，将其设置为true。

将状态变量添加到类中。如果为true，并且选择了一个数字，则在写入数字之前清除显示并将其设置为false

---

单击“=”时，将其设置为真。

根据简要回顾，似乎需要引入一个变量来跟踪计算器的状态，然后在按下“相等”按钮时，将状态设置为计算值。然后，在数字按钮（0-9）中，需要检查状态变量，并附加或替换显示文本

根据简要回顾，似乎需要引入一个变量来跟踪计算器的状态，然后当按下“相等”按钮时，将状态设置为计算值。然后，在数字按钮（0-9）中，需要检查状态变量，并附加或替换显示文本

根据简要回顾，似乎需要引入一个变量来跟踪计算器的状态，然后当按下“相等”按钮时，将状态设置为计算值。然后，在数字按钮（0-9）中，需要检查状态变量，并附加或替换显示文本

根据简要回顾，似乎需要引入一个变量来跟踪计算器的状态，然后当按下“相等”按钮时，将状态设置为计算值。然后，在数字按钮（0-9）中，需要检查状态变量，并附加或替换显示文本

创建此全局变量

private bool equationComplete = false;

将此添加到“等于”按钮的末尾

equationComplete = true;

将此添加到每个数字按钮的开头单击

if (equationComplete) DisplayTextBox.Text = "";

将此添加到每个数字按钮的末尾，然后单击事件处理程序

equationComplete = false;

---

创建此全局变量

private bool equationComplete = false;

将此添加到“等于”按钮的末尾

equationComplete = true;

将此添加到每个数字按钮的开头单击

if (equationComplete) DisplayTextBox.Text = "";

将此添加到每个数字按钮的末尾，然后单击事件处理程序

equationComplete = false;

---

创建此全局变量

private bool equationComplete = false;

将此添加到“等于”按钮的末尾

equationComplete = true;

将此添加到每个数字按钮的开头单击

if (equationComplete) DisplayTextBox.Text = "";

将此添加到每个数字按钮的末尾，然后单击事件处理程序

equationComplete = false;

---

创建此全局变量

private bool equationComplete = false;

将此添加到“等于”按钮的末尾

equationComplete = true;

将此添加到每个数字按钮的开头单击

if (equationComplete) DisplayTextBox.Text = "";

将此添加到每个数字按钮的末尾，然后单击事件处理程序

equationComplete = false;

---

向类中添加一个布尔变量，该变量表示操作是否刚刚完成的标志，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最初，该值将为

false

，因为首次创建计算器时没有发生任何事情

现在，在equal button事件处理程序的末尾，将标志设置为true，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最后，在数字按钮的事件处理程序中，检查

operationJustCompleted

标志是否为true，如果为true，则清除文本并将operationJustCompleted标志重置为

false

；像这样：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

---

向类中添加一个布尔变量，该变量表示操作是否刚刚完成的标志，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最初，该值将为

false

，因为首次创建计算器时没有发生任何事情

现在，在equal button事件处理程序的末尾，将标志设置为true，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最后，在数字按钮的事件处理程序中，检查

operationJustCompleted

标志是否为true，如果为true，则清除文本并将operationJustCompleted标志重置为

false

；像这样：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

---

向类中添加一个布尔变量，该变量表示操作是否刚刚完成的标志，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最初，该值将为

false

，因为首次创建计算器时没有发生任何事情

现在，在equal button事件处理程序的末尾，将标志设置为true，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最后，在数字按钮的事件处理程序中，检查

operationJustCompleted

标志是否为true，如果为true，则清除文本并将operationJustCompleted标志重置为

false

；像这样：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

---

向类中添加一个布尔变量，该变量表示操作是否刚刚完成的标志，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最初，该值将为

false

，因为首次创建计算器时没有发生任何事情

现在，在equal button事件处理程序的末尾，将标志设置为true，如下所示：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

最后，在数字按钮的事件处理程序中，检查

operationJustCompleted

标志是否为true，如果为true，则清除文本并将operationJustCompleted标志重置为

false

；像这样：

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    Double FirstNumber;
    string mathOperator = "";
    bool operationJustCompleted = false;

private void EqualButton_Click(object sender, EventArgs e)
{
    // Logic for calculation

    operationJustCompleted = true;
}

private void Button1_Click(object sender, EventArgs e)
{
    if(operationJustCompleted)
    {
        DisplayTextBox.Text = String.Empty;
        operationJustCompleted = false;
    }
    DisplayTextBox.Text = DisplayTextBox.Text + "1";
}

    private void EqualButton_Click(object sender, EventArgs e)
    {
        ClearDisplayBeforeNextTextEntry = true;
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        // New code
        ClearText();
        // Old code
        DisplayTextBox.Text = DisplayTextBox.Text + "1";
    }

    // Same for all other number buttons as above

    private void ClearText()
    {
        if (ClearDisplayBeforeNextTextEntry)
        {
            DisplayTextBox.Text = "";
            ClearDisplayBeforeNextTextEntry = false;
        }
    }

---

正如大卫·阿诺所说，s