C# 中HttpWebRequest 获取网页信息阻塞问题，只能提交一次

Question

没有释放
req.Abort();
wr.close();我以前遇到过

Answer 1

另外补充一下 如果你要提取大量网页在catch里也要释放一下

Answer 2

修改之后的代码”：  public String dopost(String keyword)
        {
            Encoding myEncoding = Encoding.GetEncoding("gb2312");
            string param = HttpUtility.UrlEncode("hl", myEncoding) + "=" + HttpUtility.UrlEncode("zh-CN", myEncoding) + "&"
                + HttpUtility.UrlEncode("num", myEncoding) + "=" + HttpUtility.UrlEncode("100", myEncoding) + "&"
                + HttpUtility.UrlEncode("q", myEncoding) + "=" + HttpUtility.UrlEncode(keyword, myEncoding);
            byte[] postBytes = Encoding.ASCII.GetBytes(param);            HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("http://www.google.com.hk/search?"+param);
            req.Method = "GET";
            req.ContentType = "application/x-www-form-urlencoded;charset=gb2312";
            req.ContentLength = postBytes.Length;
                    
            WebResponse wr = null;
            try
            {
                wr = req.GetResponse();
            }
            catch
            {
                label_status.Text = "网络连接错误，没插网线吧！";
            }            using (wr)
            {
                StreamReader sr = new StreamReader(wr.GetResponseStream(),Encoding.GetEncoding("gb2312"));
                String str=sr.ReadToEnd();
                req.Abort();
                wr.Close();
                return str;
            }
        }
依然不行 ，提示是wr为空

Answer 3

req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
req.ContentLength = bs.Length;
using (Stream reqStream = req.GetRequestStream())
{
   
}
using (WebResponse wr = req.GetResponse())
{} 

Answer 4

我是 直接 get方式的 ，非要采用post 方式？
请明示

Answer 5

            HttpWebRequest MyRequest = null;
            HttpWebResponse MyResponse = null;
            try
            {
                if (url.IndexOf("www.tudou.com/programs/view/") > 0)
                {
                    return checkSame(url);
                }
                else
                {                    MyRequest = (HttpWebRequest)HttpWebRequest.Create(url);
                    MyRequest.Timeout = 15000;
                    MyRequest.AllowAutoRedirect = false;
                    MyResponse = (HttpWebResponse)MyRequest.GetResponse();                    if (MyResponse.StatusCode == HttpStatusCode.OK)
                    {
                        Stream resStream = MyResponse.GetResponseStream();
                        StreamReader webRstrem = new StreamReader(resStream, Encoding.Default);
                        StringBuilder sb = new StringBuilder();
                        string Result = "";
                        while ((Result = webRstrem.ReadLine()) != null)
                        {
                            sb.Append(Result);
                            if (Result.IndexOf("</title>") > 0)
                            {
                                break;
                            }
                        }
                        string haha = sb.ToString();                        webRstrem.Close();
                        resStream.Close();
                        MyResponse.Close();
                        MyRequest.Abort();                        string regex = @"(?<=<title.*>)([\s\S]*)(?=</title>)";
                        System.Text.RegularExpressions.Regex ex = new System.Text.RegularExpressions.Regex(regex, System.Text.RegularExpressions.RegexOptions.IgnoreCase);
                        string rile = ex.Match(haha).Value.Trim();
                        if (rile == "网页无法找到")
                        {
                            return false;
                        }
                        else
                        {
                            return true;
                        }
                    }
                    else
                    {
                        MyResponse.Close();
                        MyRequest.Abort();
                        return false;
                    }
                }
            }
            catch (Exception e)
            {
                if (MyResponse != null)
                {
                    MyResponse.Close();
                }
                if (MyRequest != null)
                {
                    MyRequest.Abort();
                }
                if (e.Message.ToString() == "操作超时")
                {
                    time++;
                    if (time >= 3)
                    {
                        return false;
                    }
                    System.Threading.Thread.Sleep(500);
                    return checkTudou(url);
                }
            }

Answer 6

摘自我以前写的一个类   vs2005 sql2003下没问题