Question

如何从异步方法中获取结果？

    async Task<string> Get(string Url)
    {
        HttpClient httpClient = new HttpClient();
        httpClient.MaxResponseContentBufferSize = 10485760;
        httpClient.DefaultRequestHeaders.Add("user-agent", "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW64; Trident/6.0)");
        HttpResponseMessage response = await httpClient.GetAsync(Url);
        return await response.Content.ReadAsStringAsync();
    }

调用方法

var a = Get(address).Result;
Outbox.Text = a;

当试图得到结果时，我得到输出winodow “线程0xdf4已退出，代码为0（0x0）”

并没有发生任何事情

但我可以通过这种方式得到结果

    async Task Get(string Url)
    {
        HttpClient httpClient = new HttpClient();
        httpClient.MaxResponseContentBufferSize = 10485760;
        httpClient.DefaultRequestHeaders.Add("user-agent", "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW64; Trident/6.0)");
        HttpResponseMessage response = await httpClient.GetAsync(Url);
        Outbox.Text = response.Content.ReadAsStringAsync().Result;
    }

并通过这种方式调用方法

var a = Get(address);

我在Windows Phone 8.1上尝试此代码。感谢。

Answer 1

在大多数情况下，当调用异步方法时，您应该等待它：

var a = await Get(address);
Outbox.Text = a;

调用.Result在技术上是有效的，但是你要冻结调用线程，这有时会导致死锁（就像你的样本中一样）。

从Windows Phone中的异步方法获取结果

1 个答案: