使用异步C＃时，“任务Home.HomeButton_ClickAsync具有错误的返回类型”

Question

代码：

    private async Task HomeMoreButton_ClickAsync(object sender, EventArgs e)
    {
        InfoLabel_YearOfRelease.Show();

        using (var httpClient = new HttpClient())
        {
            var Json = await httpClient.GetStringAsync("http://www.omdbapi.com/?apikey=......=" + InfoNameOfShow.Text
             + "&type=" + InfoTypeOfShow.Text.ToLower());
            var ShowsExtendedInfo = new JavaScriptSerializer().Deserialize<ShowsExtendedInfo>(Json);

            InfoLabel_YearOfRelease.Text = ShowsExtendedInfo.Year;
        }
    }

错误：

  

CS0407 '任务Home.HomeMoreButton_ClickAsync（object，EventArgs）'具有错误的返回类型

在线：

  

this.HomeMoreButton.Click + = new   System.EventHandler（ this.HomeMoreButton_ClickAsync ）;

---

我四处走动，但从未遇到此错误，也找不到任何在线帮助我的东西。

Answer 1

事件处理程序必须为async void 参见Async/Await - Best Practices in Asynchronous Programming