不管什么东西，但凡太大了，总是让人又爱又恨啊！（很有道理的样子，大家鼓掌└(￣ ￣└)(┘￣ ￣)┘）
猿：老板，现在这社会啊，真是浮躁啊，之前还是什么1080P，然后就到了2K，现在又到了4K……他们是想把毛孔都看清楚？
老板：能不能做？
猿：已经做好了啊，但是……反正这次我们能说会道的X经理也没能忽……说服客户。
老板：是什么问题嘛，说出来我帮你想想办法。（老板真是好人啊，语重心长）
猿(ノへ￣、)：客户不是升级了4K摄像机吗，哎哟，那玩意儿，老长了，就跟火箭筒似的，扛起来那感觉(ง •̀_•́)ง，真是拉风……
老板：咳咳……
猿：嗯，4K，拍出来的照片分辨率4096x2160，一张图片就有30多M，然后……我们的程序挂了，内存崩了。╮(￣▽￣")╭
老板：嗯，这个问题嘛……
猿：昨晚我加班到凌晨三点，各种调试，各种查资料，终于搞定了，今天早上让小X过去更换了，然后……
老板：辛苦了，办公室里有吃的，晚上加班尽管吃！
猿：(￣▽￣")……
猿：然后内存是没爆了，但是大图出来的使用有2~3秒的空白……也不能操作……X经理正在给我们争取时间……
老板：这样啊，我给你一个我朋友的电话，他也是搞软件的，很牛Ｘ的……
嗯，各位童鞋，看到这里就应该明白，对话已经结束。这就开始我们的代码……
ＸＡＭＬ我们就简单点：用ListView做个列表，一个用于显示大图的Image，一个遮罩层Border
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="420"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<ListView x:Name="lvImages" ScrollViewer.CanContentScroll="False" SelectionChanged="lvImages_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<Image Source="{Binding Converter={StaticResource ImageSourceConverter}, Mode=OneTime,ConverterParameter=400}" Width="400" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ScrollViewer Grid.Column="1" >
<ScrollViewer.Background>
<ImageBrush ImageSource="{Binding SelectedItem, ElementName=lvImages,Converter={StaticResource ImageSourceConverter}}" Stretch="Uniform"/>
</ScrollViewer.Background>
<Image Name="bigImage" MouseWheel="bigImage_MouseWheel" RenderTransformOrigin="0.5,0.5">
<Image.RenderTransform>
<ScaleTransform x:Name="scale"/>
</Image.RenderTransform>
</Image>
</ScrollViewer>
<Border Name="conver" Background="#60000000" Visibility="Hidden" Grid.ColumnSpan="2">
<Path Data="M30.330999,48.228C31.299783,48.422099 32.299767,48.531501 33.330949,48.531501 34.360932,48.531501 35.363415,48.422099 36.335999,48.228L36.335999,66.659003 30.330999,66.659003z M43.268281,44.750998L52.394999,60.832034 47.175917,63.796996 38.038999,47.713359C39.994767,47.070048,41.753928,46.067427,43.268281,44.750998z M23.209264,44.598998C24.700174,45.940215,26.447487,46.971526,28.389,47.638133L19.002135,63.568 13.824999,60.518466z M47.700966,38.078002L63.757998,47.260428 60.782928,52.473998 44.726998,43.300773C46.044784,41.78905,47.055174,40.028529,47.700966,38.078002z M18.923298,37.936999C19.546999,39.89281,20.5418,41.665007,21.844,43.188594L5.7032509,52.206 2.7709999,46.960906z M18.4298,30.342997C18.240998,31.305102 18.131697,32.306304 18.131697,33.328299 18.131697,34.360797 18.237098,35.373698 18.435,36.3502L0.0077514648,36.370997 0,30.365096z M66.659098,30.285998L66.666998,36.294497 48.231798,36.313998C48.4272,35.347804 48.531301,34.352805 48.531301,33.328002 48.531301,32.294097 48.4272,31.284898 48.227999,30.308202z M60.963728,14.451999L63.895998,19.696799 47.743868,28.718999C47.120075,26.764499,46.123985,24.996299,44.817999,23.474099z M5.8831024,14.181999L21.936999,23.357735C20.616765,24.868125,19.607615,26.627213,18.960647,28.578999L2.9039993,19.403264z M47.663984,3.0889991L52.839998,6.1383522 43.456712,22.064999C41.96595,20.723838,40.213178,19.687466,38.276999,19.020785z M19.487081,2.8649989L28.617,18.94893C26.66778,19.585601,24.902254,20.590758,23.394619,21.910998L14.261999,5.8297189z M30.330999,0L36.335999,0 36.335999,18.430999C35.363416,18.2357 34.36093,18.127599 33.330949,18.127599 32.299765,18.127599 31.299782,18.2357 30.330999,18.430999z"
Stretch="Uniform" Margin="200" Fill="Red" RenderTransformOrigin="0.5,0.5">
<Path.RenderTransform>
<RotateTransform x:Name="rotate" Angle="0"/>
</Path.RenderTransform>
</Path>
</Border>
</Grid>
后台代码：
private void Window_Loaded(object sender, RoutedEventArgs e)
{
//高清大图，你懂的。
var path = Combine(AppDomain.CurrentDomain.BaseDirectory, "images");//using static System.IO.Path;
var files = Directory.GetFiles(path);
lvImages.ItemsSource = files;
} private async void lvImages_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
//在选中项更改时进行处理，
if (lvImages.SelectedIndex > -)
{
//选中的项
var current = e.AddedItems[]; bigImage.Source = null; //坐和放宽，很快就好。
conver.Visibility = Visibility.Visible;
rotate.BeginAnimation(RotateTransform.AngleProperty, new DoubleAnimation(, TimeSpan.FromMilliseconds())
{ RepeatBehavior = RepeatBehavior.Forever }); //await一下
try
{
var source = await Task.Run<ImageSource>(() =>
{
var p = current.ToString();
var s = new BitmapImage();
s.BeginInit();
s.CacheOption = BitmapCacheOption.OnLoad;
//打开文件流
using (var stream = File.OpenRead(p))
{
s.StreamSource = stream;
s.EndInit();
//这一句很重要，少了UI线程就不认了。
s.Freeze();
}
return s;
});
//出炉
bigImage.Source = source;
}
catch { }
//好了，不用转了
rotate.BeginAnimation(RotateTransform.AngleProperty, null);
conver.Visibility = Visibility.Hidden;
}
else
{
var s = bigImage.Source;
s = null;
bigImage.Source = null;
}
} private void bigImage_MouseWheel(object sender, MouseWheelEventArgs e)
{
//高清大图嘛，当然要放大了仔细看看
var d = e.Delta / 1000.0;
if (scale.ScaleX + d < )
{
scale.ScaleX = scale.ScaleY = ;
return;
}
scale.ScaleX += d;
scale.ScaleY += d;
}
一个简单的ImageSourceConverter：
public class ImageSourceConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value == null)
return value;
var source = new BitmapImage();
source.BeginInit();
source.UriSource = new Uri(value.ToString(), UriKind.Absolute);
//设置解码的分辨率大小，也就是搞个缩略图
source.DecodePixelWidth = parameter != null ? int.Parse(parameter.ToString()) : ;
source.EndInit();
return source; } public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
看图：