Get it before filtering the post tag.

modules/blogging/src/Volo.Blogging.Application/Volo/Blogging/Posts/PostAppService.cs

@@ -36,19 +36,19 @@ namespace Volo.Blogging.Posts
             var userDictionary = new Dictionary<Guid, BlogUserDto>();
             var postDtos = new List<PostWithDetailsDto>(ObjectMapper.Map<List<Post>, List<PostWithDetailsDto>>(posts));
 
-            if (tag != null)
+            foreach (var postDto in postDtos)
             {
-                postDtos = await FilterPostsByTag(postDtos, tag);
+                postDto.Tags = await GetTagsOfPost(postDto.Id);
             }
 
-            foreach (var postDto in postDtos)
+            if (tag != null)
             {
-                postDto.CommentCount = await _commentRepository.GetCommentCountOfPostAsync(postDto.Id);
+                postDtos = await FilterPostsByTag(postDtos, tag);
             }
 
             foreach (var postDto in postDtos)
             {
-                postDto.Tags = await GetTagsOfPost(postDto.Id);
+                postDto.CommentCount = await _commentRepository.GetCommentCountOfPostAsync(postDto.Id);
             }
 
             foreach (var postDto in postDtos)