/// <summary>
/// 异步HTTP请求辅助类
/// </summary>
public class HttpHelper
{
public class HttpArgs
{
public HttpWebRequest request { set; get; }
public string post { set; get; }
}
public HttpHelper(string userAgent)
{
UserAgent = userAgent;
}
public string Referer { set; get; }
public string UserAgent { set; get; }
public object Tag { set; get; }
public String subString { set; get; }
private HttpResponseDelegate httpResponseDelegate;
public delegate void HttpResponseDelegate(HttpHelper sender, Stream stream);
/// <summary>
/// 开始一个请求
/// </summary>
/// <param name="url">网址</param>
/// <param name="post">如果为NULL，则为GET请求</param>
/// <param name="resp">回调方法</param>
public void request(string url, string post, HttpResponseDelegate resp)
{
Random random = new Random();
if (url.Contains("?b") || url.Contains("&b") || url.Contains("notic"))
{
request(new Uri(url), post, resp);
}
else
{
if (url.Contains("?"))
{
subString = url + "&b=" + random.Next(1000, 9000).ToString();
}
else
{
subString = url + "?b=" + random.Next(1000, 9000).ToString();
}
request(new Uri(subString), post, resp);
}
}
/// <summary>
/// 开始一个请求
/// </summary>
/// <param name="url">网址</param>
/// <param name="post">如果为NULL，则为GET请求</param>
/// <param name="resp">回调方法</param>
public void request(Uri url, string post, HttpResponseDelegate resp)
{
httpResponseDelegate = resp;
HttpWebRequest request = HttpWebRequest.Create(url) as HttpWebRequest;
WebHeaderCollection whc = new WebHeaderCollection();
if (Referer != null)
{
request.Headers[HttpRequestHeader.Referer] = Referer;
}
request.UserAgent = UserAgent;
if (post != null)
{
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
request.BeginGetRequestStream(requestReady, new HttpArgs() { request = request, post = post });
}
else
{
request.BeginGetResponse(responseReady, request);
}
}
/// <summary>
/// 准备
/// </summary>
/// <param name="result"></param>
private void requestReady(IAsyncResult result)
{
HttpArgs obj = result.AsyncState as HttpArgs;
HttpWebRequest request = obj.request;
String webpost = obj.post;
var stream = request.EndGetRequestStream(result);
using (StreamWriter writer = new StreamWriter(stream))
{
writer.Write(webpost);
writer.Flush();
}
request.BeginGetResponse(responseReady, request);
}
private void responseReady(IAsyncResult result)
{
HttpWebRequest webrequest = result.AsyncState as HttpWebRequest;
try
{
WebResponse response = webrequest.EndGetResponse(result);
using (var stream = response.GetResponseStream())
{
if (httpResponseDelegate != null)
{
httpResponseDelegate.Invoke(this, stream);
}
}
response.Close();
}
catch (Exception ex)
{
var msg = ex.Message;
if (httpResponseDelegate != null)
{
httpResponseDelegate.Invoke(this, null);
}
}
}
}