- 一个数据绑定的例子
<Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}" x:Name="gridBook" >
<Grid.RowDefinitions >
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<StackPanel Grid.Row="0" Orientation="Horizontal">
<TextBlock Text="书名：" FontSize="96" VerticalAlignment="Center" Margin="30,0,0,0"/>
<TextBlock x:Name="txtBlockName" Foreground="Red" FontSize="96" Text="{Binding Name}" VerticalAlignment="Center"/>
</StackPanel>
<StackPanel Grid.Row="1" Orientation="Horizontal">
<TextBlock Text="价格：" FontSize="96" VerticalAlignment="Center" Margin="30,0,0,0"/>
<TextBlock x:Name="txtBlockPrice" Foreground="Red" FontSize="96" Text="{Binding Price}" VerticalAlignment="Center"/>
</StackPanel>
<StackPanel Grid.Row="2" Orientation="Horizontal">
<TextBlock Text="类型：" FontSize="96" VerticalAlignment="Center" Margin="30,0,0,0"/>
<TextBlock x:Name="txtBlockType" Foreground="Red" FontSize="96" Text="{Binding Type}" VerticalAlignment="Center"/>
</StackPanel>
</Grid>namespace App1
{
/// <summary>
/// An empty page that can be used on its own or navigated to within a Frame.
/// </summary>
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
}
/// <summary>
/// Invoked when this page is about to be displayed in a Frame.
/// </summary>
/// <param name="e">Event data that describes how this page was reached. The Parameter
/// property is typically used to configure the page.</param>
protected override void OnNavigatedTo(NavigationEventArgs e)
{
var book = new Book("XAML Primer", 24.4, "移动开发");
gridBook.DataContext = book;
}
}
public class Book
{
public string Name { get; set; }
public double Price { get; set; }
public string Type { get; set; }
public Book(string name, double price, string type)
{
Name = name;
Price = price;
Type = type;
}
}
}运行结果为：
在XAML中，先给Grid起名字，然后在里面定义了三行，每一行里面分别定义了一个StackPanel，用来存放数据标签和数据内容。
数据绑定时，使用{binding perperty}这样的方式绑定数据，由于Book里面有三个成员变量，且分别为Name，Price和Type，所以这里的Property分别设为这三个值即可。
在代码中，使用DataContext来指定数据源，对于每个控件可以使用这个来绑定，因此可以使用代码：
txtName.DataContext = book; txtPrice.DataContext = book; txtType.DataContext = book;
来指定数据源，写起来实际是很不方便的，因为如果控件多了，每个都要这么指定那岂不是很繁琐，所以这里可以采用一点小技巧使用一条语句即可。根据数据绑定里面的一个规则：子类继承父类的数据源，我们可以很方便地写出完成这个功能的代码，因为三个控件都在一个Grid里面，所以在这里直接把Grid的数据源指定为book即可，那么其所有的子控件的默认数据源就都是book了。
- 数据绑定的模式
数据绑定有三种模式：OneTime，OneWay和TwoWay
1）OnewTime：绑定的数据源发生了变化，绑定的目标控件的UI也不会发生改变，可以用来给出任意时刻的数据库的快照
2）OneWay:数据源发生了改变，UI也会跟着更新，但是UI更新了，数据源不会更新，这个是单向的。
3）TwoWay：数据源和UI控件任何一个修改了，另外一个会跟着发生改变。
使用的时候，指定数据源的格式为：
<Text="{Binding Name, Mode=TwoWay}” />一般而言，TextBlock使用OneWay，而TextBox使用TwoWay。需要注意的是，上面所说的OneWay和TwoWa，y如果你直接指定模式，然后绑定数据，当数据源发生变化的时候，你会发现UI界面上所绑定的控件并不会随之而变化，难道我忘记了什么？答案是，当你使用OneWay和TwoWay的时候，如果你希望你的界面能够跟着数据源实时变化，那么你需要做一些“额外”做的工作了。1）类首先必须继承INotifyPropertyChanged类；
2）声明对象：PropertyChangedEventHandler PropertyChanged;在更改属性时引发该事件。
3）数据源设置调用事件响应函数，如：
private int _Age; public int Age { get { return this._Age; } set { this._Age = value; notifyPropertyChanged(); } }4）实现响应函数，触发NotifyPropertyChanged事件，例子如:private void NotifyPropertyChanged(String info) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(info)); } }
- 数据类型转换
在数据绑定过程中，数据往往并不是直接兼容的，所以这个时候就需要使用到数据转换了，方法是构建一个实现了IValueConverter类的类，在这类类里面实现Convert函数和可选的ConvertBack函数.
- 数据绑定实例
XAML文件：
<Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}"> <StackPanel HorizontalAlignment="Left"> <ComboBox x:Name="comboBox" ItemsSource="{Binding}" Foreground="Black" FontSize="30" Height="50" Width="550"> <ComboBox.ItemTemplate> <DataTemplate> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="*"></ColumnDefinition> <ColumnDefinition Width="*"></ColumnDefinition> <ColumnDefinition Width="*"></ColumnDefinition> <ColumnDefinition Width="*"></ColumnDefinition> </Grid.ColumnDefinitions> <TextBox Text="Name:" Grid.Column="0"/> <TextBox Text="{Binding Name}" Grid.Column="1"/> <TextBox Text="Title:" Grid.Column="2"/> <TextBox Text="{Binding Title}" Grid.Column="3"/> </Grid> </DataTemplate> </ComboBox.ItemTemplate> </ComboBox> <StackPanel Orientation="Horizontal" HorizontalAlignment="Stretch"> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition></ColumnDefinition> <ColumnDefinition></ColumnDefinition> </Grid.ColumnDefinitions> <Button x:Name="btnChangeData" Grid.Column="0" Content="ClickMeChangeName" HorizontalAlignment="Left" FontSize="48" Click="btnChangeData_Click"></Button> <Button x:Name="btnGetData" Grid.Column="1" Content="ClickMeGetName" HorizontalAlignment="Right" FontSize="48" Click="btnGetData_Click"></Button> </Grid> </StackPanel> <TextBox x:Name="txtBindingData" Text="{Binding Name, Mode=TwoWay}" FontSize="68"></TextBox> </StackPanel> </Grid>C#源代码：using System; using System.Collections.Generic; using System.Collections.ObjectModel; using System.ComponentModel; using System.IO; using System.Linq; using Windows.Foundation; using Windows.Foundation.Collections; using Windows.UI.Popups; using Windows.UI.Xaml; using Windows.UI.Xaml.Controls; using Windows.UI.Xaml.Controls.Primitives; using Windows.UI.Xaml.Data; using Windows.UI.Xaml.Input; using Windows.UI.Xaml.Media; using Windows.UI.Xaml.Navigation; // The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234238 namespace BindingDemo { /// <summary> /// An empty page that can be used on its own or navigated to within a Frame. /// </summary> public sealed partial class MainPage : Page { private Employee employee = new Employee {Name="good", Title="hust"}; public MainPage() { this.InitializeComponent(); } /// <summary> /// Invoked when this page is about to be displayed in a Frame. /// </summary> /// <param name="e">Event data that describes how this page was reached. The Parameter /// property is typically used to configure the page.</param> protected override void OnNavigatedTo(NavigationEventArgs e) { comboBox.ItemsSource = Employee.GetEmployees(); txtBindingData.DataContext = employee; } private void btnChangeData_Click(object sender, RoutedEventArgs e) { employee.Name = new DateTime().ToString("yyyy-MM-dd"); } private async void btnGetData_Click(object sender, RoutedEventArgs e) { MessageDialog dlg = new MessageDialog(employee.Name, "btnGetData_Click"); dlg.Commands.Add(new UICommand("Ok")); await dlg.ShowAsync(); } } public class Employee : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; private string _name; public string Name { get { return _name; } set { _name = value; RaisePropertyChanged(); } } private string _title; public string Title { get { return _title; } set { _title = value; RaisePropertyChanged(); } } private void RaisePropertyChanged(string caller = "" ) { if (PropertyChanged != null ) { PropertyChanged( this, new PropertyChangedEventArgs( caller ) ); } } public static ObservableCollection<Employee> GetEmployees() { var employees = new ObservableCollection<Employee>(); employees.Add( new Employee() { Name = "Washington", Title = "President 1" } ); employees.Add( new Employee() { Name = "Adams", Title = "President 2" } ); employees.Add( new Employee() { Name = "Jefferson", Title = "President 3" } ); employees.Add( new Employee() { Name = "Madison", Title = "President 4" } ); employees.Add( new Employee() { Name = "Monroe", Title = "President 5" } ); return employees; } } }