计算器:十进制数字除外

它可以用整数进行加、减、乘和除，但不能用十进制数进行加、减、乘和除。sum1变量有问题，就像给它们赋一个小数时，它们的格式是错误的。这是因为它们被声明为double，但我不知道如何用不同的方式来写。

double sum1 = 0;
    double sum2 = 0;
    bool plusButtonClicked = false;
    bool subButtonClicked = false;
    bool multButtonClicked = false;
    bool divButtonClicked = false;
    public MainWindow()
    {
        InitializeComponent();
    }
    private void NumberValidationTextBox(object sender, TextCompositionEventArgs e)
    {
        Regex regex = new Regex("[^0-9]+");
        e.Handled = regex.IsMatch(e.Text);
    }
    private void one_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += one.Content;
    }
    private void two_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += two.Content;
    }
    private void three_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += three.Content;
    }
    private void four_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += four.Content;
    }
    private void five_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += five.Content;
    }
    private void six_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += six.Content;
    }
    private void seven_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += seven.Content;
    }
    private void eight_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += eight.Content;
    }
    private void nine_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += nine.Content;
    }
    private void zero_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Text += zero.Content;
    }
    private void add_Click(object sender, RoutedEventArgs e)
    {
        sum1 += double.Parse(numEnt.Text);
        numEnt.Clear();
        plusButtonClicked = true;
        subButtonClicked = false;
        multButtonClicked = false;
        divButtonClicked = false;
    }
    private void sub_Click(object sender, RoutedEventArgs e)
    {
        sum1 += double.Parse(numEnt.Text);
        numEnt.Clear();
        plusButtonClicked = false;
        subButtonClicked = true;
        multButtonClicked = false;
        divButtonClicked = false;
    }
    private void mult_Click(object sender, RoutedEventArgs e)
    {
        sum1 += double.Parse(numEnt.Text);
        numEnt.Clear();
        plusButtonClicked = false;
        subButtonClicked = false;
        multButtonClicked = true;
        divButtonClicked = false;
    }
    private void div_Click(object sender, RoutedEventArgs e)
    {
        sum1 += double.Parse(numEnt.Text);
        numEnt.Clear();
        plusButtonClicked = false;
        subButtonClicked = false;
        multButtonClicked = false;
        divButtonClicked = true;
    }
    private void deci_Click(object sender, RoutedEventArgs e)
    {
        string currentInput = numEnt.Text;
        bool pointFound = false;
        for (int i = 0; i < currentInput.Length; i++)
        {
            if (currentInput[i] == '.')
                pointFound = true;
        }
        if (pointFound == false)
            numEnt.Text += ".";
    }
    private void equal_Click(object sender, RoutedEventArgs e)
    {
        if (plusButtonClicked == true)
        {
            sum2 = sum1 + double.Parse(numEnt.Text);
            result.Text = sum2.ToString();
            sum1 = 0;
        }
        if (subButtonClicked == true)
        {
            sum2 = sum1 - double.Parse(numEnt.Text);
            result.Text = sum2.ToString();
            sum1 = 0;
        }
        if (multButtonClicked == true)
        {
            sum2 = sum1 * double.Parse(numEnt.Text);
            result.Text = sum2.ToString();
            sum1 = 0;
        }
        if (divButtonClicked == true)
        {
            sum2 = sum1 / double.Parse(numEnt.Text);
            result.Text = sum2.ToString();
            sum1 = 0;
        }
    }
    private void clear_Click(object sender, RoutedEventArgs e)
    {
        numEnt.Clear();
        calculations.Clear();
        result.Clear();
    }


}

double sum1 =0.0 ;
private void add_Click(object sender, RoutedEventArgs e)
{
    sum1 += double.Parse(numEnt.Text);
    numEnt.Clear();
    plusButtonClicked = true;
    subButtonClicked = false;
    multButtonClicked = false;
    divButtonClicked = false;
}
private void sub_Click(object sender, RoutedEventArgs e)
{
    sum1 -= double.Parse(numEnt.Text);
    numEnt.Clear();
    plusButtonClicked = false;
    subButtonClicked = true;
    multButtonClicked = false;
    divButtonClicked = false;
}
private void mult_Click(object sender, RoutedEventArgs e)
{
    sum1 *= double.Parse(numEnt.Text);
    numEnt.Clear();
    plusButtonClicked = false;
    subButtonClicked = false;
    multButtonClicked = true;
    divButtonClicked = false;
}
private void div_Click(object sender, RoutedEventArgs e)
{
    sum1 /= double.Parse(numEnt.Text);
    numEnt.Clear();
    plusButtonClicked = false;
    subButtonClicked = false;
    multButtonClicked = false;
    divButtonClicked = true;
}
private void deci_Click(object sender, RoutedEventArgs e)
{
    string currentInput = numEnt.Text;
    bool pointFound = false;
    //for (int i = 0; i < currentInput.Length; i++)
    //{
        if(currentInput.Contains("."))//if (currentInput[i] == '.')
            pointFound = true;
    //}
    if (pointFound == false)
        numEnt.Text += ".";
}

 double.Parse(string, IFormatProvider) 

var currentCulture = System.Globalization.CultureInfo.InstalledUICulture;
var numberFormat = (System.Globalization.NumberFormatInfo) currentCultur .NumberFormat.Clone();
numberFormat .NumberDecimalSeparator = ".";