WPF值转换器的使用

<Window x:Class="CollectionBinding.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:data="clr-namespace:ClassLibrary;assembly=ClassLibrary"
        xmlns:local="clr-namespace:CollectionBinding"
        Title="MainWindow" Height="523.038" Width="361.701">
    <Window.Resources>
        <ObjectDataProvider IsAsynchronous="True" ObjectType="{x:Type data:StoreDB}" MethodName="GetProducts" x:Key="DataProvider"></ObjectDataProvider>
        <local:PriceConverter x:Key="PriceConverter"></local:PriceConverter>
        <local:ImageConverter x:Key="ImageConverter"></local:ImageConverter>
<local:PriceToBrushConverter Min="10" Max="100" x:Key="PriceToBrushConverter"></local:PriceToBrushConverter>
    </Window.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <ListBox Margin="3" Grid.Row="0" Name="lstProducts" Height="120" 
                 ScrollViewer.VerticalScrollBarVisibility="Visible" ItemsSource="{Binding Source={StaticResource DataProvider}}" DisplayMemberPath="ModelName"></ListBox>
        <StackPanel Margin="3" Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right">
            <Button Margin="3" MinWidth="100" Name="btnGetProducts" Click="btnGetProducts_Click_1">GetProducts</Button>
        </StackPanel>
<Grid Margin="3" Name="grid" Grid.Row="2" DataContext="{Binding ElementName=lstProducts,Path=SelectedItem}"
              Background="{Binding Path=UnitCost, Converter={StaticResource PriceToBrushConverter}}">
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="*"></RowDefinition>
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto"></ColumnDefinition>
                <ColumnDefinition></ColumnDefinition>
            </Grid.ColumnDefinitions>
            <TextBlock Margin="3" Grid.Row="0" Grid.Column="0">CategoryID:</TextBlock>
            <TextBox Name="txtCategoryID" Margin="3" Grid.Row="0" Grid.Column="1" Text="{Binding Path=CategoryID}"></TextBox>


            <TextBlock Margin="3" Grid.Row="1" Grid.Column="0">ModelNumber:</TextBlock>
            <TextBox Name="txtModelNumber" Margin="3" Grid.Row="1" Grid.Column="1" Text="{Binding Path=ModelNumber}"></TextBox>


            <TextBlock Margin="3" Grid.Row="2" Grid.Column="0">ModelName:</TextBlock>
            <TextBox Name="txtModelName" Margin="3" Grid.Row="2" Grid.Column="1" Text="{Binding Path=ModelName}"></TextBox>


            <TextBlock Margin="3" Grid.Row="3" Grid.Column="0">ProductImage:</TextBlock>
            <Border Grid.Row="3" Grid.Column="1" Margin="3" BorderBrush="Black" BorderThickness="1"  Width="100" Height="100" >
                <Image Source="{Binding Path=ProductImage,Converter={StaticResource ImageConverter}}"></Image>


            </Border>
           
            <TextBlock Margin="3" Grid.Row="4" Grid.Column="0">UnitCost:</TextBlock>
 <TextBox Name="txtUnitCost" Margin="3" Grid.Row="4" Grid.Column="1" Text="{Binding Path=UnitCost,Converter={StaticResource PriceConverter}}">
                
            </TextBox>
            
            <TextBox Name="txtDescription" Margin="3" Grid.Row="5" Grid.Column="0" Grid.ColumnSpan="2" TextWrapping="Wrap"
                     Text="{Binding Path=Description}" ScrollViewer.VerticalScrollBarVisibility="Visible"></TextBox>
        </Grid>
    </Grid>
</Window>

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;
using System.Windows.Media.Imaging;


namespace CollectionBinding
{
    [ValueConversion(typeof(string), typeof(BitmapImage))]
    public class ImageConverter : IValueConverter
    {
        string rootPath = Directory.GetCurrentDirectory();
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            string imagePath = Path.Combine(rootPath, value.ToString());
            return new BitmapImage(new Uri(imagePath));
        }
        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
    

}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;


namespace CollectionBinding
{
    [ValueConversion(typeof(decimal),typeof(string))]
    public class PriceConverter:IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            decimal price = (decimal)value;
            return price.ToString("C", culture);
        }


        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            string price = value.ToString();
            decimal result = 0;
            if (decimal.TryParse(price,System.Globalization.NumberStyles.Any,culture,out result))
            {
                return result;
            }
            return value;
        }
    }

}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;
using System.Windows.Media;


namespace CollectionBinding
{
    [ValueConversion(typeof(decimal),typeof(Brush))]
    class PriceToBrushConverter:IValueConverter
    {
        public decimal Max { get; set; }
        public decimal Min { get; set; }
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
         decimal price = (decimal)value;
            if (price < Min)
            {
                return new SolidColorBrush(Colors.Yellow);
            }
            else if (price<Max)
            {
                return new SolidColorBrush(Colors.Green);
            }
            else
            {
                return new SolidColorBrush(Colors.Red);
            }
        }


        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
         throw new NotImplementedException();
        }
    }
}