Wpf DataTemplate

Question

我已经为ListView定义了一个DataTemplate来显示fileInfo详细信息。这是DataTemplate

<DataTemplate x:Key="srchFileListTemplate">
    <StackPanel>
        <WrapPanel>
            <TextBlock FontWeight="Bold" FontFamily="Century Gothic"
                Text="FileName :"/>
            <TextBlock Margin="10,0,0,0" FontWeight="Bold"
                FontFamily="Century Gothic" Text="{Binding Path=Name}"/>
        </WrapPanel>
        <WrapPanel>
            <TextBlock FontFamily="Century Gothic" Text="FilePath :"/>
            <TextBlock Margin="20,0,0,0" FontFamily="Century Gothic"
                Text="{Binding Path = DirectoryName}"/>
        </WrapPanel>
        <WrapPanel>
            <TextBlock FontFamily="Century Gothic" Text="File Size :"/>
            <TextBlock Margin="20,0,0,0" FontFamily="Century Gothic"
                Text="{Binding Path = Length}"/>
            <TextBlock Text="Bytes"/>
        </WrapPanel>
        <WrapPanel>
            <TextBlock FontFamily="Century Gothic" Text="File Extension:"/>
            <TextBlock Margin="20,0,0,0" FontFamily="Century Gothic"
                Text="{Binding Path = Extension}"/>
        </WrapPanel>
    </StackPanel>
</DataTemplate> 

ListView的ImagesSource为List<FileInfo>

我必须根据文件的扩展名在列表中添加一个自定义图标。是否可以将扩展传递给一个方法，以获取现有DataTemplate中的图标路径？

Answer 1

你需要一个转换器：

[ValueConversion(typeof(string), typeof(ImageSource))]
public class FileIconConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        string fileName = value as string;
        if (fileName == null)
            return null;
        return IconFromFile(fileName);
    }

    private ImageSource IconFromFile(string fileName)
    {
        // logic to get the icon based on the filename
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        // The opposite conversion doesn't make sense...
        throw new NotImplementedException();
    }

}

然后，您需要在资源中声明转换器的实例：

<Window.Resources>
    <local:FileIconConverter x:Key="iconConverter" />
</Window.Resources>

并在绑定中使用它，如下所示：

<Image Source="{Binding FullName, Converter={StaticResource iconConverter}}" />