如何在Windows 8应用程序中获取html源代码

Question

在Windows 8中，我尝试从URL获取html源代码：

private void loadingDatafromWeb(string URL)
{
    HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL);
    request.BeginGetResponse(new AsyncCallback(ReadCallbackLoadingData),request);
}

和

private void ReadCallbackLoadingData(IAsyncResult asynchronousResult)
{
    string myPageSource;
    HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
    HttpWebResponse response =   (HttpWebResponse)request.EndGetResponse(asynchronousResult);
    using (StreamReader myWebSource = new StreamReader(response.GetResponseStream()))
    {
        myPageSource = myWebSource.ReadToEnd();
    }

我想在函数loadingDatafromWeb中获取字符串myPageSource，但我不能这样做。请告诉我怎么做？

Answer 1

您可以使用新的.Net 4.5功能，并使用await关键字呼叫：

private void loadingDatafromWeb(string URL)
{
    HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL);
    string html = await ReadData(new Uri(request));
}

你的助手方法是：

private async Task<string> ReadData(Uri uri)
{
     string result;

     // Get your response synchronously (do not forget to enscope WebResponse
     // and other Streams inside 'usings').

     return result;
}