Question

我是Xamarin.Forms的新手。我尝试制作该应用程序，但尚未成功。现在的代码由2个输入和一个“开始”按钮组成。我无法将其绑定到C＃代码并返回答案。

namespace FirstApp
{
public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
    }
    private void Calculate
    {
        Double Num1;
        Double Num2;
        Answer = (Num1 + Num2).ToString();
    }
}

<FlexLayout>
    <Entry Text="{Binding Num1}"></Entry>
    <Entry Text="{Binding Num2}"></Entry>
    <Button Text="Go" Clicked="Calculate"></Button>
    <Label Text="{Binding Answer}"></Label>
</FlexLayout>

Answer 1

在xaml文件中尝试一下：

<Window x:Class="AddTwoNumbersCSharp.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:AddTwoNumbersCSharp"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="2*"/>
            <ColumnDefinition Width="2*"/>
            <ColumnDefinition Width="1*"/>
        </Grid.ColumnDefinitions>
        <TextBox Name="TextBox1" AcceptsReturn="False" AcceptsTab="False" Grid.Column="0" Grid.Row="0" FontSize="20"/>
        <TextBox Name="TextBox2" AcceptsReturn="False" AcceptsTab="False" Grid.Column="1" Grid.Row="0" FontSize="20"/>
        <Button Name="GoButton" Click="GoButton_Click" Grid.Column="2" Content="Go" Grid.Row="0" FontSize="20"/>
        <TextBlock Name="ResultText" Grid.Row="1" FontSize="20"/>
    </Grid>
</Window>

然后在C＃文件中输入以下内容：

using System;
using System.Windows;

namespace AddTwoNumbersCSharp
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void GoButton_Click(object sender, RoutedEventArgs e)
        {
            Decimal num1;
            Decimal num2;
            bool success = Decimal.TryParse(TextBox1.Text, out num1);
            bool success2 = Decimal.TryParse(TextBox2.Text, out num2);
            if (!success || !success2)
            {
                ResultText.Text = "Not a valid number!";
            }
            else
            {
                ResultText.Text = (num1 + num2).ToString();
            }
        }
    }
}

使用XAML和C＃，如何制作一个将两个数字相加的应用程序？

1 个答案: