我不知道为什么我得到零除的异常。我一般对编程都是新手，无法弄清楚我做错了什么。对不起，冗长的代码，我想我已经尽可能多地删除了它，但仍然给出了异常。 这是C＃代码...
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
namespace CalculationApp
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class MainPage : ContentPage
{
public MainPage()
{
InitializeComponent();
BreakEvenCalculation();
}
private void BreakEvenCalculation()
{
var purchaseprice = Decimal.Parse(PurchasePriceEntry.Text);
var purchaseweight = Decimal.Parse(PurchaseWeightEntry.Text);
var purchasefreight = Decimal.Parse(PurchaseFreightEntry.Text);
var medicineimplants = Decimal.Parse(MedicineImplantsEntry.Text);
var costofgain = Decimal.Parse(CostOfGainEntry.Text);
var poundstillsell = Decimal.Parse(PoundsTillSellEntry.Text);
var deathloss = Decimal.Parse(DeathLossEntry.Text);
var saleweight = Decimal.Parse(SaleWeightEntry.Text);
var salefreight = Decimal.Parse(SaleFreightEntry.Text);
var breakeven = Decimal.Parse(BreakEvenEntry.Text);
var purchasedollars = purchaseprice * purchaseweight;
var feedcost = costofgain * poundstillsell;
poundstillsell = saleweight - purchaseweight;
var costs = (purchasedollars + purchasefreight + medicineimplants + feedcost + deathloss + salefreight);
breakeven = costs / saleweight; //throws exception.... System.DivideByZeroException: Attempted to divide by zero
//breakeven = costs / (saleweight + 1); //correctly equals 1.111302549965541
//breakeven = costs * saleweight; //correctly equals 2338125.00
//breakeven = saleweight; //correctly equals 1450.00
//breakeven = costs; //correctly equals 1612.50
////////////breakeven should equal 1.112068965517241
BreakEvenEntry.Text = breakeven.ToString();
}
private void PurchasePriceEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void PurchaseWeightEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void PurchaseFreightEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void MedicineImplantsEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void CostOfGainEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void PoundsTillSellEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void DeathLossEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void SalePriceEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void SaleWeightEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
private void SaleFreightEntry_Completed(object sender, TextChangedEventArgs e)
{
BreakEvenCalculation();
}
}
这是xaml代码...
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage x:Class="CalculationApp.MainPage"
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:CalculationApp"
xmlns:customentry="clr-namespace:CustomEntry">
<StackLayout Padding="0" BackgroundColor="AliceBlue" Orientation="Vertical">
<Label Text="CalculationApp" TextColor="Black" FontAttributes="Italic" FontSize="Large" TextDecorations="Underline" Scale="1.5"
Margin="0,15,0,10" HorizontalOptions="CenterAndExpand" VerticalTextAlignment="Center" VerticalOptions="CenterAndExpand"/>
<Grid ColumnSpacing="0" RowSpacing="5">
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width=".6*" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Label Text="Purchase Price" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="0" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap"/>
<Label Text="Purchase Weight" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="1" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Purchase Freight" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="2" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Medicine/Implants" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="3" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Cost of Gain" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="4" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Pounds Till Sell" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="5" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Death Loss" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="6" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Sale Price" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="7" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Sale Weight" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="8" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Label Text="Sale Freight" TextColor="Black" FontAttributes="Bold" Margin="0,0,25,0" Scale="1.2"
Grid.Column="0" Grid.Row="9" HorizontalTextAlignment="End" VerticalTextAlignment="Center" LineBreakMode="NoWrap" />
<Entry x:Name="PurchasePriceEntry" Text="{Binding Source={x:Reference PurchasePriceStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="0" HorizontalTextAlignment="Center" Keyboard="Numeric" ReturnType="Next" VerticalOptions="End" MaxLength="5"
TextChanged="PurchasePriceEntry_Completed"/>
<Entry x:Name="PurchaseWeightEntry" Text="{Binding Source={x:Reference PurchaseWeightStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="1" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="PurchaseWeightEntry_Completed" />
<Entry x:Name="PurchaseFreightEntry" Text="{Binding Source={x:Reference PurchaseFreightStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="2" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="PurchaseFreightEntry_Completed" />
<Entry x:Name="MedicineImplantsEntry" Text="{Binding Source={x:Reference MedicineImpantsStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="3" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="MedicineImplantsEntry_Completed" />
<Entry x:Name="CostOfGainEntry" Text="{Binding Source={x:Reference CostofGainStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="4" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="CostOfGainEntry_Completed" />
<Entry x:Name="PoundsTillSellEntry" Text="1000" TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="5" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center" IsEnabled="False" />
<Entry x:Name="DeathLossEntry" Text="{Binding Source={x:Reference DeathLossStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="6" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="DeathLossEntry_Completed" />
<Entry x:Name="SalePriceEntry" Text="{Binding Source={x:Reference SalePriceStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="7" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="SalePriceEntry_Completed" />
<Entry x:Name="SaleWeightEntry" Text="{Binding Source={x:Reference SaleWeightStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="8" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="SaleWeightEntry_Completed" />
<Entry x:Name="SaleFreightEntry" Text="{Binding Source={x:Reference SaleFreightStepper}, Path=Value}"
TextColor="DarkSlateGray" FontAttributes="Bold" BackgroundColor="Ivory" TranslationX="3"
Grid.Column="1" Grid.Row="9" HorizontalTextAlignment="Center" Keyboard="Numeric" VerticalOptions="Center"
TextChanged="SaleFreightEntry_Completed" />
<Stepper x:Name="PurchasePriceStepper" Grid.Column="2" Grid.Row="0" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="5" Minimum=".01" Increment=".01" Value="1.75" />
<Stepper x:Name="PurchaseWeightStepper" Grid.Column="2" Grid.Row="1" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="2000" Minimum="1" Increment="1" Value="550"/>
<Stepper x:Name="PurchaseFreightStepper" Grid.Column="2" Grid.Row="2" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="100" Minimum="0" Increment=".25" Value="10"/>
<Stepper x:Name="MedicineImpantsStepper" Grid.Column="2" Grid.Row="3" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="500" Minimum="0" Increment=".25" Value="25.00"/>
<Stepper x:Name="CostofGainStepper" Grid.Column="2" Grid.Row="4" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="3" Minimum="0" Increment=".01" Value="0.65"/>
<Stepper x:Name="DeathLossStepper" Grid.Column="2" Grid.Row="6" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="500" Minimum="0" Increment="1" Value="20"/>
<Stepper x:Name="SalePriceStepper" Grid.Column="2" Grid.Row="7" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="5" Minimum="0" Increment=".01" Value="1.25"/>
<Stepper x:Name="SaleWeightStepper" Grid.Column="2" Grid.Row="8" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="5000" Minimum="0" Increment="5" Value="1450.00"/>
<Stepper x:Name="SaleFreightStepper" Grid.Column="2" Grid.Row="9" HorizontalOptions="Center" VerticalOptions="Center" Scale=".75" TranslationX="3" Maximum="100" Minimum="0" Increment=".25" Value="10"/>
</Grid>
<Grid Padding="10" ColumnSpacing="5" RowSpacing="10" VerticalOptions="FillAndExpand">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Label Text="Break Even" x:Name="BreakEvenLabel" TextColor="Black" FontSize="Medium" FontAttributes="Bold" Grid.Column="0" Grid.Row="0" HorizontalTextAlignment="Center" VerticalOptions="Center" LineBreakMode="NoWrap" />
<Label Text="Profit" TextColor="Black" FontSize="Medium" FontAttributes="Bold" Grid.Column="1" Grid.Row="0" HorizontalTextAlignment="Center" VerticalOptions="Center" LineBreakMode="NoWrap" />
<Entry x:Name="BreakEvenEntry" Text="125" FontSize="Large" TextColor="Black" Grid.Column="0" Grid.Row="1" FontAttributes="Bold" BackgroundColor="Ivory" IsEnabled="False" HorizontalTextAlignment="Center" VerticalOptions="Center" />
<Entry x:Name="ProfitEntry" TextColor="Black" FontSize="Large" Grid.Column="1" Grid.Row="1" FontAttributes="Bold" BackgroundColor="Ivory" IsEnabled="False" HorizontalTextAlignment="Center" VerticalOptions="Center" />
</Grid>
</StackLayout>
</ContentPage>
该异常发生在C＃中的这一行上...
breakeven = costs / saleweight;
正如您所看到的，我尝试了几种不同的方式更改代码，以弄清楚发生了什么。在我看来，要获得除以零的例外，销售权重必须为零，但是如果我将代码更改为简单阅读...
breakeven = saleweight;
Xamarin.Forms BreakEvenEntry给我正确的销售权重...所以它不为零吧？
我想念什么？我在做什么错？？
感谢您的提前帮助！
答案 0 :(得分：2)
“费用”被创建为浮点数或双精度数，需要明确地定义为十进制，以匹配解析的十进制变量。
decimal costs = (purchasedollars + [...]
Here is a link关于C＃的整数vs浮点除法：
“如果一个操作数是十进制，则另一个操作数既不能是float也不是double，因为float和double都不能隐式转换为十进制。必须将float或double操作数显式转换为十进制类型。”
（与上述建议相反，您可以考虑将变量解析为double或float。结果相同：float除法而不是整数除法。）
我试图重现您的错误，但无法执行。但是，让我想起了在Python 2.7中我找到一个similar error的时间。