部分的缓存管理器

PixivFSUWP/Data/CacheManager.cs

@@ -0,0 +1,49 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Windows.Storage;
+
+namespace PixivFSUWP.Data
+{
+    //用来管理缓存
+    public static class CacheManager
+    {
+        //临时目录
+        private static StorageFolder tmpFolder = ApplicationData.Current.TemporaryFolder;
+
+        //获取临时目录，确保目录存在
+        private static async Task<StorageFolder> getCacheFolder()
+        {
+            var cacheFolder = await tmpFolder.TryGetItemAsync("Cache");
+            if (cacheFolder == null) return await tmpFolder.CreateFolderAsync("Cache");
+            else return cacheFolder as StorageFolder;
+        }
+
+        //清除缓存
+        public static async Task ClearCache()
+        {
+            var cacheFolder = await tmpFolder.TryGetItemAsync("imgCache");
+            if (cacheFolder != null) await cacheFolder.DeleteAsync();
+        }
+
+        //得到目录大小
+        private static async Task<long> getFolderSize(StorageFolder target)
+        {
+            var getFileSizeTasks = from file
+                                   in await target.CreateFileQuery().GetFilesAsync()
+                                   select file.GetBasicPropertiesAsync().AsTask();
+            var fileSizes = await Task.WhenAll(getFileSizeTasks);
+            var getFolderSizetTasks = from folder
+                                      in await target.CreateFolderQuery().GetFoldersAsync()
+                                      select getFolderSize(folder);
+            var folderSizes = await Task.WhenAll(getFolderSizetTasks);
+            return fileSizes.Sum(i => (long)i.Size) + folderSizes.Sum();
+        }
+
+        //得到缓存目录大小
+        public static async Task<long> GetCacheSize()
+            => await getFolderSize(await getCacheFolder());
+    }
+}

PixivFSUWP/PixivFSUWP.csproj

@@ -152,6 +152,7 @@
     <Compile Include="Data\FollowingIllustsCollection.cs" />
     <Compile Include="Data\IllustCommentItem.cs" />
     <Compile Include="Data\IllustDetail.cs" />
+    <Compile Include="Data\CacheManager.cs" />
     <Compile Include="Data\RankingIllustsCollection.cs" />
     <Compile Include="Data\RecommendIllustsCollection.cs" />
     <Compile Include="Data\OverAll.cs" />