Silverlight用户界面及基本后台代码编程
其实，从分层角度来看，就客户端Silverlight项目这边来看，也可进一步分为若干子层。例如，.xaml文件可看作最上面的展示层，相应的后台代码文件.xaml.cs则又是一层。
Silverlight 3项目自动生成的主页面文件为MainPage.xaml。现在，打开此文件，并输入如下标记代码：
<UserControl
xmlns:data="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data" x:Class="S3RIACustomSample.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:DesignWidth="Auto" d:DesignHeight="Auto">
<Grid x:Name="LayoutRoot">
<StackPanel Orientation="Vertical">
<data:DataGrid IsReadOnly="True" Name="productsGrid" Height="Auto" Width="Auto"
SelectionChanged="DataGrid_SelectionChanged"/>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Competitor's price" Margin="2"/>
<TextBlock x:Name="compPrice" Margin="2"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<Button Click="Button_Click" Content="Discount" x:Name="discountButton" Margin="2"/>
<TextBox x:Name="discountPercent" Text="10" Margin="2,2"/>
<TextBlock Text="%" Margin="2,5,0,2"/>
</StackPanel>
</StackPanel>
</Grid>
</UserControl>
上面的XAML代码非常简单，不再赘述。
相应的后台代码文件MainPage.xaml.cs的内容如下所示：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
//下面是新添加的命名空间引用
using System.Windows.Ria.Data;
using RIA=S3RIACustomSample.Web;
namespace S3RIACustomSample
{
public partial class MainPage : UserControl
{
RIA.Catalog catalog = new RIA.Catalog();//创建Catalog对象实例
public MainPage()
{
InitializeComponent();
productsGrid.ItemsSource = catalog.Products;
var query = from p in catalog.GetProductQuery()
where p.ListPrice > 3000 select p;
catalog.Load(query);//把满足要求的产品数据加载到DataGrid控件
}
private void Button_Click(object sender, RoutedEventArgs e)
{
RIA.Product selectedProduct = (RIA.Product)productsGrid.SelectedItem;
if (selectedProduct != null) {
//int percentage = int.Parse(discountPercent.Text);
//selectedProduct.DiscountProduct(percentage);
//catalog.SubmitChanges();
}
}
private void DataGrid_SelectionChanged(object sender, SelectionChangedEventArgs e) {
RIA.Product selectedProduct = (RIA.Product)productsGrid.SelectedItem;
if (selectedProduct != null) {
//catalog.GetCompetitorsPrice(selectedProduct,
// (invokeOperation) =>
// {
// compPrice.Text = invokeOperation.Value.ToString();
// }, null);
}
}
}
