.net core并发请求发送HttpWebRequest的坑解决

在framework中，大量并发 httpwebrequest 需要设置一个最大连接数

servicepointmanager.defaultconnectionlimit = 200;

但是在.net core中却无效，因为core不使用 servicepointmanager 管理连接数，在core中只有使用httpclient，httpcilentfactory来管理连接数，如果在core中使用 servicepointmanager 不但不起作用，并且大量并发使用 httpwebrequest 会导致 iis 直接假死，所以在core中，只能使用 httpclient 和 httpcilentfactory这一条路可走

在core中的startup注册一个httpclient的名字

    public void configureservices(iservicecollection services)
    {
      services.addhttpclient("httpclientfactorydemo");
    }

然后在controller中创建

using system;
using system.collections.generic;
using system.net.http;
using system.net.http.headers;
using system.text;
using system.threading.tasks;
using system.web;
using microsoft.aspnetcore.mvc;
 
namespace httpclientfactorydemo.controllers
{
  [route("api/[controller]")]
  [apicontroller]
  public class valuescontroller : controllerbase
  {
    private readonly ihttpclientfactory _httpclientfactory;
 
    public valuescontroller(ihttpclientfactory httpclientfactory)
    {
      _httpclientfactory = httpclientfactory;
    }
 
    public static string urlencode(string temp, encoding encoding)
    {
      stringbuilder stringbuilder = new stringbuilder();
      for (int i = 0; i < temp.length; i++)
      {
        string t = temp[i].tostring();
        string k = httputility.urlencode(t, encoding);
        if (t == k)
        {
          stringbuilder.append(t);
        }
        else
        {
          stringbuilder.append(k.toupper());
        }
      }
      return stringbuilder.tostring();
    }
 
    [httpget]
    public async task<actionresult> get()
    {
      encoding.registerprovider(codepagesencodingprovider.instance);
      string xmlcontent = "<?xml version=\"1.0\" encoding=\"gbk\" standalone=\"yes\"?><xml><version>1</version><ins_cd>08a9999999</ins_cd><mchnt_cd>0002900f0370588</mchnt_cd><term_id></term_id><random_str>93b4efa6d0d84808a76355ff0f7a178d</random_str><sign>g1+tbpyevwsqjej9x7zrobrtfti/itujweeyl3at/9xlfd844jv2wb/gnvkuevp890tf1ub+eate1qbyhsu97cpqr6riudxqw2nnjkzbzsg00c1d8070szpf4c1hksufhlr2npn+7dvianlcjrfztgotq/wtcarrl/sjijeaxyg=</sign><order_type>alipay</order_type><goods_des>卡盟测试</goods_des><goods_detail></goods_detail><addn_inf></addn_inf><mchnt_order_no>2018121302054468584629</mchnt_order_no><curr_type></curr_type><order_amt>1</order_amt><term_ip>127.0.0.1</term_ip><txn_begin_ts>20181213020544</txn_begin_ts><goods_tag></goods_tag><auth_code>288232051781304899</auth_code><sence>1</sence><reserved_sub_appid></reserved_sub_appid><reserved_limit_pay></reserved_limit_pay></xml>";
      xmlcontent = urlencode(xmlcontent, encoding.getencoding("gbk"));
 
      dictionary<string, string> nvs = new dictionary<string, string> { { "req", xmlcontent } };
      encoding encoding = encoding.getencoding("gbk");
      stringbuilder buffer = new stringbuilder();
      int i = 0;
      idictionary<string, string> sortedparams = new sorteddictionary<string, string>(nvs);
      foreach (keyvaluepair<string, string> kvp in nvs)
      {
        buffer.appendformat(i > 0 ? "&{0}={1}" : "{0}={1}", kvp.key,
          urlencode(kvp.value, encoding.getencoding("gbk")));
        i++;
      }
      byte[] postbody = encoding.getbytes(buffer.tostring());
 
      var client = _httpclientfactory.createclient("httpclientfactorydemo");
      var request = new httprequestmessage
      {
        requesturi = new uri("https://spay.fuiou.com/commonquery"),
        method = httpmethod.post,
        content = new bytearraycontent(postbody),
      };
 
      request.content.headers.contenttype =
        new mediatypeheadervalue("application/x-www-form-urlencoded");
 
      return ok(await client.sendasync(request));
 
    }
  }
}

总结

以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作具有一定的参考学习价值，如果有疑问大家可以留言交流，谢谢大家对的支持。