使用await和async返回字符串列表

• 我在组织租户azure环境中部署了一个ASP.NET（4.5）网站 .

• 它具有向/从网络位置上载/下载/删除文件（任何类型）的功能（我们称之为nas驱动器），例如\ nas8782 \某某\ ABC \

• 上传/下载/删除工作正常（参见下面的代码） . 我们使用由Azure团队创建的CloudSdk.Azure库 .

• nasClient.UploadAsync

• nasClient.DownloadAsync

• nasClient.DeleteAsync

• nasClient.ListFilesAsync

FileService.cs

using CloudSdk.Azure;

private string userId = ConfigurationManager.AppSettings["userId"].ToString();
    private string userPassword = ConfigurationManager.AppSettings["userPassword"].ToString();
    private string baseNasLocation = ConfigurationManager.AppSettings["baseNasLocation"].ToString();
    string env = ConfigurationManager.AppSettings["env"].ToString().ToUpper();

public async Task Upload(string fileName, string fileToSave, string projectID)
    {
        var nasClient = new NasClient(userId, userPassword);
        var localFiles = new List<string>();
        localFiles.Add(fileToSave);
        await nasClient.UploadAsync(baseNasLocation + env + @"\" + projectID + @"\", localFiles);
}
public async Task Download(string fileToDownload, string projectID)
    {
        var nasClient = new NasClient(userId, userPassword);
        Stream stream2 = nasClient.DownloadAsync(baseNasLocation + env + @"\" + projectID + @"\" + fileToDownload).Result;
        var appPath2 = HostingEnvironment.MapPath("~\\TempUpload");
        var localFullPath2 = string.Format("{0}\\{1}", appPath2, fileToDownload);
        using (var fileStream2 = System.IO.File.Create(localFullPath2))
        {
            stream2.CopyTo(fileStream2);
        }
}


 public async Task Delete(string fileToDelete, string projectID)
    {
        var nasClient = new NasClient(userId, userPassword);
        Task stream2 = nasClient.DeleteAsync(baseNasLocation + env + @"\" + projectID + @"\" + fileToDelete);
}

我从default.aspx.cs页面调用这些函数

private void Download(string fileName)
    {
        FileService fObj = new FileService();
        var task = Task.Run(async () => { await fObj.Download(fileName, projectId.ToString()); });
        task.Wait();
    }
 private void Delete(string fileName)
    {
        FileService fObj = new FileService();
        var task = Task.Run(async () => { await fObj.Delete(fileName, projectId.ToString()); });
        task.Wait();
    }
private void Upload(string fileName, string fileToSave)
    {
        FileService fObj = new FileService();
  var task = Task.Run(async () => { await fObj.Upload(fileName, fileToSave, projectId.ToString()); });
        task.Wait();
    }

ISSUE

• 这个CloudSdk.Azure库有另一个函数调用ListFilesAsync，它获取所提供路径中存在的所有文件的列表 .

我使用下面的代码来做同样但无法得到它 .

如果我调用这个Fileservice方法

没有异步和等待 - 它运行但保持运行并且永远不会返回结果 .

public  Task<string> ListFileNames(string projectID)
        {
            var nasClient = new NasClient(userId, userPassword);
            string nasPath = baseNasLocation + env + @"\" + projectID + @"\"; 

            var content =  nasClient.ListFilesAsync(nasPath).Result;
            //return content;
            return JsonConvert.DeserializeObject <Task<string>> (content); 
        }

使用Async和await - 它抛出编译错误> 'string'不包含'GetAwaiter'的定义，并且没有扩展方法'GetAwaiter'接受类型为'string'的第一个参数（您是否缺少using指令或程序集引用？）

public async Task<string> ListFileNames(string projectID)
        {
            var nasClient = new NasClient(userId, userPassword);
            string nasPath = baseNasLocation + env + @"\" + projectID + @"\"; 

            var content = await nasClient.ListFilesAsync(nasPath).Result;
            //return content;
            return JsonConvert.DeserializeObject <Task<string>> (content); 
        }

我如何从aspx.cs页面调用此方法>如何获得结果？

var task = Task.Run(async () => { await fObj.ListFileNames(projectId.ToString()); });
        task.Wait();

很抱歉这个问题很长，我只想尽可能多地描述一下 . I am new to this await and async, will really appreciate all the help.