带有WPF的简易桌面计算器

Question

我用WPF开发了这个简单的桌面计算器。只是想知道，你们认为我的编码风格，这方面的项目和任何代码重构需要减少重复的代码？

public partial class MainWindow : Window
{
    double lastNumber;
    string lastNumberString, selectedValue;
    LastInputType lastInputType;
    bool firstZero;
    Button selectedBtn;

    private void Init(bool isEqualPressed = false, bool isOperatorPressed = false)
    {

        if (!isEqualPressed)
            resultLabel.Content = "0";

        if (!isOperatorPressed)
            resultLabelExp.Content = "";


        // This reset is similar with after key in operator reset but without the above line
        firstZero = false;
        lastNumberString = "";
        lastNumber = 0;
        lastInputType = LastInputType.Operator;
    }

    public MainWindow()
    {
        InitializeComponent();

        acButton.Click += AcButton_Click;
        negativeButton.Click += NegativeButton_Click;
        percentageButton.Click += PercentageButton_Click;
        equalButton.Click += EqualButton_Click;

        Init();
    }

    private void EqualButton_Click(object sender, RoutedEventArgs e)
    {
        if (resultLabelExp.Content.ToString().Trim() != "" && lastInputType != LastInputType.Operator)
        {
            resultLabel.Content = MathBodmas.EvalExpression(resultLabelExp.Content.ToString().ToCharArray()).ToString();
            Init(true);
        }
    }

    private void PercentageButton_Click(object sender, RoutedEventArgs e)
    {
        if (double.TryParse(resultLabel.Content.ToString(), out lastNumber))
        {
            lastNumber = lastNumber / 100;
            resultLabel.Content = lastNumber.ToString();
        }
    }

    private void NegativeButton_Click(object sender, RoutedEventArgs e)
    {
        if (double.TryParse(resultLabel.Content.ToString(), out lastNumber))
        {
            lastNumber = lastNumber * -1;
            resultLabel.Content = lastNumber.ToString();
        }
    }

    private void AcButton_Click(object sender, RoutedEventArgs e)
    {            
        Init();
    }

    private void OperationButton_Click(object sender, RoutedEventArgs e)
    {
        selectedBtn = sender as Button;
        selectedValue = selectedBtn.Content.ToString();

        if (lastInputType == LastInputType.Operator)
        {
            if (resultLabelExp.Content.ToString() == "")
            {
                // Do nothing
            }
            else
            {                    
                ReplaceLastChar(selectedValue);
            }
        }
        else
        {
            AppendExp(selectedValue);
        }

        Init(false, true);
    }

    private void DecimalButton_Click(object sender, RoutedEventArgs e)
    {
        selectedBtn = sender as Button;
        selectedValue = selectedBtn.Content.ToString();

        if (lastNumberString.Contains("."))
        {
            // Do nothing
        }
        else
        {
            if (lastNumberString == "")
            {
                lastNumberString += "0.".ToString();
                resultLabelExp.Content += "0.".ToString();
            }
            else
            {
                // Append
                AppendExp(selectedValue);                    
            }
        }
        firstZero = false;
    }

    private void NumberButton_Click(object sender, RoutedEventArgs e)
    {
        selectedBtn = sender as Button;
        selectedValue = selectedBtn.Content.ToString();

        switch (lastInputType)
        {
            case LastInputType.Operator:
            case LastInputType.Zero:
                // firstZero value is assigned at Zero button click handler 
                if (firstZero)
                {                     
                    ReplaceLastChar(selectedValue);
                    firstZero = false;
                }
                else
                {
                    // Append
                    AppendExp(selectedValue);
                }

                break;
            case LastInputType.Number:
                // Append
                AppendExp(selectedValue);

                break;
            default:
                break;
        }
        lastInputType = LastInputType.Number;
    }

    private void ZeroButton_Click(object sender, RoutedEventArgs e)
    {
        selectedBtn = sender as Button;
        selectedValue = selectedBtn.Content.ToString();

        if (lastNumberString == "")
        {
            // First zero assigned                
            AppendExp(selectedValue);

            firstZero = true;
            // Do nothing
        }
        else if (lastNumberString.Length == 1 && lastNumberString == "0")
        {
            firstZero = true;
            // Do nothing
            // To block 00
        }
        else
        {
            // Append. i.e. 100
            AppendExp(selectedValue);
        }

        lastInputType = LastInputType.Zero;
    }

    private void AppendExp(string _selectedValue)
    {
        lastNumberString += _selectedValue.ToString();
        resultLabelExp.Content += _selectedValue.ToString();
    }

    private void ReplaceLastChar(string _selectedValue)
    {
        // Replace
        lastNumberString = _selectedValue;

        // Extract whole string without last char using substring.
        resultLabelExp.Content = resultLabelExp.Content.ToString().Substring(0, resultLabelExp.Content.ToString().Length - 1);

        resultLabelExp.Content += lastNumberString;
    }
}

public enum LastInputType
{
    Zero, Number, Operator
}

完整的源代码可在我的github - https://github.com/ngaisteve1/CalculatorWPF上找到。

按要求提供XAML文件

<Window x:Class="Calculator.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:Calculator"
    mc:Ignorable="d"
    Title="MainWindow" Height="525" Width="350">

<Grid Margin="10">
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*"/>
        <ColumnDefinition Width="*"/>
        <ColumnDefinition Width="*"/>
        <ColumnDefinition Width="*"/>
    </Grid.ColumnDefinitions>
    <Grid.RowDefinitions>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
    </Grid.RowDefinitions>
    <Label x:Name="resultLabelExp"
           Content="0"
           HorizontalAlignment="Right"
           VerticalAlignment="Bottom"
           Grid.ColumnSpan="4" FontSize="30"
           Foreground="Gray"  />
    <Label x:Name="resultLabel"
           Content="0"
           HorizontalAlignment="Right"
           VerticalAlignment="Bottom"
           Grid.ColumnSpan="4" FontSize="40"
           Grid.Row="1"/>
    <Button x:Name="acButton"
            Style="{StaticResource additionalButtonsStyle}"
            Content="AC"
            Grid.Row="2"/>
    <Button x:Name="negativeButton"
            Style="{StaticResource additionalButtonsStyle}"
            Content="+/-"
            Grid.Row="2"
            Grid.Column="1" IsEnabled="False"/>
    <Button x:Name="percentageButton"
            Style="{StaticResource additionalButtonsStyle}"
            Content="%"
            Grid.Row="2"
            Grid.Column="2" IsEnabled="False"/>
    <Button x:Name="divisionButton"
            Click="OperationButton_Click"
            Style="{StaticResource operatorButtonsStyle}"
            Content="/"
            Grid.Row="2"
            Grid.Column="3"/>
    <Button x:Name="sevenButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="7"
            Grid.Row="3"/>
    <Button x:Name="eightButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="8"
            Grid.Row="3"
            Grid.Column="1"/>
    <Button x:Name="nineButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="9"
            Grid.Row="3"
            Grid.Column="2"/>
    <Button x:Name="multiplicationButton"
            Click="OperationButton_Click"
            Style="{StaticResource operatorButtonsStyle}"
            Content="*"
            Grid.Row="3"
            Grid.Column="3"/>
    <Button x:Name="fourButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="4"
            Grid.Row="4"/>
    <Button x:Name="fiveButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="5"
            Grid.Row="4"
            Grid.Column="1"/>
    <Button x:Name="sixButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="6"
            Grid.Row="4"
            Grid.Column="2"/>
    <Button x:Name="minusButton"
            Click="OperationButton_Click"
            Style="{StaticResource operatorButtonsStyle}"
            Content="-"
            Grid.Row="4"
            Grid.Column="3"/>
    <Button x:Name="oneButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="1"
            Grid.Row="5"/>
    <Button x:Name="twoButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="2"
            Grid.Row="5"
            Grid.Column="1"/>
    <Button x:Name="threeButton"
            Click="NumberButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="3"
            Grid.Row="5"
            Grid.Column="2"/>
    <Button x:Name="plusButton"
            Click="OperationButton_Click"
            Style="{StaticResource operatorButtonsStyle}"
            Content="+"
            Grid.Row="5"
            Grid.Column="3"/>
    <Button x:Name="zeroButton"
            Click="ZeroButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="0"
            Grid.Row="6"
            Grid.ColumnSpan="2"/>
    <Button x:Name="pointButton"
            Click="DecimalButton_Click"
            Style="{StaticResource numberButtonsStyle}"
            Content="."
            Grid.Row="6"
            Grid.Column="2" IsEnabled="true"/>
    <Button x:Name="equalButton"
            Style="{StaticResource operatorButtonsStyle}"
            Content="="
            Grid.Row="6"
            Grid.Column="3"/>
</Grid>

正在更改为堆栈以提高性能。

Answer 1

贴士

• 在设计WPF应用程序时使用M模式.
• 即使提供了链接，也要发布所有您想要得到的代码。

清理您的代码

• 不要只作评论用空子句。
• 当代码自我解释时，不要添加注释。
• 不要检查string和""。
• 不要在.ToString()上调用无关的string。

片段1

if (lastInputType == LastInputType.Operator) { if (resultLabelExp.Content.ToString() == "") { // Do nothing } else { ReplaceLastChar(selectedValue); } } else { AppendExp(selectedValue); }

        if (lastInputType == LastInputType.Operator)
        {
            if (resultLabelExp.Content.ToString().Any())
            {                    
                ReplaceLastChar(selectedValue);
            }
        }
        else
        {
            AppendExp(selectedValue);
        }

片段2

if (lastNumberString.Contains(".")) { // Do nothing } else { if (lastNumberString == "") { lastNumberString += "0.".ToString(); resultLabelExp.Content += "0.".ToString(); } else { // Append AppendExp(selectedValue); } }

        if (!lastNumberString.Contains("."))
        {
            if (!lastNumberString.Any())
            {
                lastNumberString += "0.";
                resultLabelExp.Content += "0.";
            }
            else
            {
                AppendExp(selectedValue);                    
            }
        }