Question

我正在尝试使用webform上的按钮来处理添加用户邮件黑猩猩。我有两个函数...一个调用async函数调用API的按钮函数。

public class MailChimpResponse
{
    public bool IsSuccessful;
    public string ReponseMessage;
}

public void SubscribeEmail(object Sender, EventArgs e)
{
    var mcResponse = SubscribeEmailAsync();
    var result = mcResponse.Result;

    if (result.IsSuccessful == true)
    {
        lblSuccess.Text = result.ReponseMessage;
        pnlSuccess.Visible = true;
    }
    else
    {
        lblError.Text = result.ReponseMessage;
        pnlError.Visible = false;
    }
}

public async Task<MailChimpResponse> SubscribeEmailAsync()
{
    IMailChimpManager mailChimpManager = new MailChimpManager(ConfigurationManager.AppSettings["testing"]);
    MailChimpResponse mcResponse = new MailChimpResponse();
    var listId = "xxxxxxxxx";

    return await Task.Run(() =>
    {
        try
        {
            var mailChimpListCollection = mailChimpManager.Members.GetAllAsync(listId).ConfigureAwait(false);

            mcResponse.IsSuccessful = true;
            mcResponse.ReponseMessage = "Success!";
        }
        catch (AggregateException ae)
        {
            mcResponse.IsSuccessful = false;
            mcResponse.ReponseMessage = ae.Message.ToString();
        }

        return mcResponse;
    });

目前填充“var mailChimpListCollection”的行应该抛出异常（我可以通过Intellisense看到它）但是它继续使用TRY而不是陷入CATCH。这只会使每次通话看起来都成功，即使不是。我在这里缺少什么？

Answer 1

根据您的说明，您尝试根据SubscribeEmailAsync调用的结果从mailChimpManager.Members.GetAllAsync(listId)方法返回响应。由于GetAllAsync方法是异步方法，而不是返回成员列表，因此它返回跟踪结果检索工作的任务。你真的错过了等待那里，你根本不需要人工Task.Run。这是我如何重写SubscribeEmailAsync方法：

public async Task<MailChimpResponse> SubscribeEmailAsync()
{
    IMailChimpManager mailChimpManager = new MailChimpManager(ConfigurationManager.AppSettings["testing"]);
    MailChimpResponse mcResponse = new MailChimpResponse();
    var listId = "xxxxxxxxx";

    try
    {
        var mailChimpListCollection = await mailChimpManager.Members.GetAllAsync(listId).ConfigureAwait(false);

        mcResponse.IsSuccessful = true;
        mcResponse.ReponseMessage = "Success!";
    }
    catch (AggregateException ae)
    {
        mcResponse.IsSuccessful = false;
        mcResponse.ReponseMessage = ae.Message.ToString();
    }

    return mcResponse;
}

希望这有帮助。

在Task.Run C＃中从try / catch返回异常

1 个答案: