MVC控制器中的异步，多个等待我需要

Question

 public async Task<ActionResult> IndexAsync()
        {
            ShowUploadFiles objFiles = new Helpers.ShowUploadFiles();
            ShowComments objComments = new Helpers.ShowComments();
            TempData["FileUploaded"] = await objFiles.ShowUploadeFiles();
            return View("Index", await objComments.GetListofCommentsfromTable());
        }

尝试在我的Controller中实现Async。   我必须调用ShowUploadFiles（）来保存在Tempdata中，并调用GetListofCommentsfromTable（）并将其作为模型传递。

我如何能够作为Tempdata和Model两者的异步同步加载。

我必须更新为

public async Task<List<BlobModel>> ShowUploadeFilesAsync()
        {
           //Some operation
           return await (List<BlobModel>);

         }

Answer 1

你可以这样做：

 public async Task<ActionResult> IndexAsync()
 {
     ShowUploadFiles objFiles = new Helpers.ShowUploadFiles();
     var showUploadeFilesTask = objFiles.ShowUploadeFiles();

     ShowComments objComments = new Helpers.ShowComments();
     var getListofCommentsfromTableTask = objComments.GetListofCommentsfromTable();

     await Task.WhenAll(showUploadeFilesTask, getListofCommentsfromTableTask);

     TempData["FileUploaded"] = showUploadeFilesTask.Result;
     return View("Index", getListofCommentsfromTableTask.Result);
 }