C# 伪造 referer 提交数据

private string SendRequest(string account, string cardNumber, string cardPass)
{
string targetUrl = https://xxx.com/;//要提交数据的目标网站
//提交的数据
string postData = string.Format("ursName={0}&userName2={0}&cardNo={1}&cardPass={2}", account, cardNumber, cardPass);

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(targetUrl);
request.Method = "POST";
request.Referer = http://www.xxx.com/jsp/xxx.jsp; byte[] bytes = Encoding.UTF8.GetBytes(postData);
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = bytes.Length;
Stream requestStream = request.GetRequestStream();
requestStream.Write(bytes, 0, bytes.Length);

HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);
string responseText = reader.ReadToEnd();

string res = "成功！";
if (responseText.Contains("errorID"))
{
string errorDetailPage = new System.Text.RegularExpressions.Regex(@"URL=(?<url>.*?)"">",
System.Text.RegularExpressions.RegexOptions.IgnoreCase | System.Text.RegularExpressions.RegexOptions.Multiline
).Match(responseText).Groups["url"].Value;

HttpWebRequest requestErrorInfo = (HttpWebRequest)WebRequest.Create(errorDetailPage);
requestErrorInfo.Method = "GET";
requestErrorInfo.Proxy = request.Proxy;
HttpWebResponse responseErrorInfo = (HttpWebResponse)requestErrorInfo.GetResponse();
StreamReader readerErrorInfo = new StreamReader(responseErrorInfo.GetResponseStream(), Encoding.Default);
string responseTextErrorInfo = readerErrorInfo.ReadToEnd();
string errorDetailMessage = new System.Text.RegularExpressions.Regex(@"<h3>(?<info>.*?)<.*?</h3>",
System.Text.RegularExpressions.RegexOptions.IgnoreCase | System.Text.RegularExpressions.RegexOptions.Multiline
).Match(responseTextErrorInfo).Groups["info"].Value.Replace(" ", "");

res = string.Format(@"失败！<br />错误信息：{0}<br /><a href=""{1}"" target=""_blank"">查看错误详情</a>", errorDetailMessage, errorDetailPage);
}

return res;
}