关于Silverlight对匿名类型数据绑定的问题及其解决方法

来源：互联网发布：西安java讲师编辑：程序博客网时间：2024/04/30 12:15

这是一个不得不说一下的问题。同样的代码在WPF应用程序中是可以工作的，而在Silverlight中却不可以。我们来看一下例子吧

1.WPF窗体标记

<Window x:Class="WpfApplication1.MainWindow"        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"        Title="MainWindow" Height="350" Width="525">    <Grid>        <ItemsControl x:Name="EmployeeList" Margin="10">            <ItemsControl.ItemTemplate>                <DataTemplate>                    <TextBlock Text="{Binding FullName}">TextBlock>                DataTemplate>            ItemsControl.ItemTemplate>        ItemsControl>    Grid>Window>

.csharpcode, .csharpcode pre{font-size: small;color: black;font-family: consolas, "Courier New", courier, monospace;background-color: #ffffff;/*white-space: pre;*/}.csharpcode pre { margin: 0em; }.csharpcode .rem { color: #008000; }.csharpcode .kwrd { color: #0000ff; }.csharpcode .str { color: #006080; }.csharpcode .op { color: #0000c0; }.csharpcode .preproc { color: #cc6633; }.csharpcode .asp { background-color: #ffff00; }.csharpcode .html { color: #800000; }.csharpcode .attr { color: #ff0000; }.csharpcode .alt {background-color: #f4f4f4;width: 100%;margin: 0em;}.csharpcode .lnum { color: #606060; }2.WPF窗体代码

using System.Windows;namespace WpfApplication1{    ///     /// Interaction logic for MainWindow.xaml    ///     public partial class MainWindow : Window    {        public MainWindow()        {            InitializeComponent();            Loaded += new RoutedEventHandler(MainWindow_Loaded);        }        void MainWindow_Loaded(object sender, RoutedEventArgs e)        {            var emps = new[]{                new{                    FullName="陈希章"                },                new{                    FullName="张三丰"                },                new{                    FullName="张无忌"                }            };            EmployeeList.ItemsSource = emps;        }    }}

然后我们来看Silverlight

1. Silverlight页面标记

<UserControl x:Class="SilverlightApplication1.MainPage"    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"    mc:Ignorable="d"    d:DesignHeight="300" d:DesignWidth="400">    <Grid x:Name="LayoutRoot" Background="White">        <ItemsControl x:Name="EmployeeList" Margin="10">            <ItemsControl.ItemTemplate>                <DataTemplate>                    <TextBlock Text="{Binding FullName}">TextBlock>                DataTemplate>            ItemsControl.ItemTemplate>        ItemsControl>    Grid>UserControl>

2. Silverlight页面代码

using System.Windows;using System.Windows.Controls;namespace SilverlightApplication1{    public partial class MainPage : UserControl    {        public MainPage()        {            InitializeComponent();            Loaded += new RoutedEventHandler(MainPage_Loaded);        }        void MainPage_Loaded(object sender, RoutedEventArgs e)        {            var emps = new[]{                new{                    FullName="陈希章"                },                new{                    FullName="张三丰"                },                new{                    FullName="张无忌"                }            };            EmployeeList.ItemsSource = emps;                    }    }}

3. 运行起来看的效果

是的，什么也没有。而如果我们不使用Binding语法，直接写好固定的文本值。例如下面这样

<UserControl x:Class="SilverlightApplication1.MainPage"    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"    mc:Ignorable="d"    d:DesignHeight="300" d:DesignWidth="400">    <Grid x:Name="LayoutRoot" Background="White">        <ItemsControl x:Name="EmployeeList" Margin="10">            <ItemsControl.ItemTemplate>                <DataTemplate>                    <TextBlock Text="Hello,World">TextBlock>                DataTemplate>            ItemsControl.ItemTemplate>        ItemsControl>    Grid>UserControl>

这说明什么问题呢？我想至少说明，绑定的操作是已经发生了，只不过没有绑定到FullName而已，或者说FullName没有数据？

好吧，那么怎么解决该问题呢？答案是在Silverlight中要用强类型的方式来保存数据。

例如下面这样的代码

using System.Windows;using System.Collections.Generic;using System.Windows.Controls;namespace SilverlightApplication1{    public partial class MainPage : UserControl    {        public MainPage()        {            InitializeComponent();            Loaded += new RoutedEventHandler(MainPage_Loaded);        }        void MainPage_Loaded(object sender, RoutedEventArgs e)        {            List emps = new List(){                new Employee(){FullName="陈希章"},                new Employee(){FullName="张三丰"},                new Employee(){FullName="张无忌"}            };            EmployeeList.ItemsSource = emps;                    }        public class Employee        {            public string FullName { get; set; }        }    }}

这样就和谐了！

【注意】这个问题有些不合情理。但我目前也没有想明白为什么，或者是不是因为某些bug导致也未可知。先解决问题吧，以后再看看。如果有哪位朋友对此有什么高见，请不吝赐教