HttpWebRequest出错 服务器提交了协议冲突. Section=ResponseHeader Detail=CR 后面必须是 LF

服务器提交了协议冲突. Section=ResponseHeader Detail=CR 后面必须是 LF  

The server committed a protocol violation. Section=ResponseHeader Detail=CR must be followed by LF 

主体意思是微软没有容忍不符合RFC 822中的httpHeader必须以CRLF结束的规定的服务器响应。 

一个解决方案是在application.config或web.config文件里加入 

  <system.net> 

    <settings> 

      <httpWebRequest useUnsafeHeaderParsing="true" /> 

    </settings> 

  </system.net> 

允许系统容忍（tolerant）只以CR或LF结尾的hearder信息 

using System.Reflection;

        bool GetAllowUnsafeHeaderParsing()
        {
            //Get the assembly that contains the internal class
            Assembly aNetAssembly = Assembly.GetAssembly(typeof(System.Net.Configuration.SettingsSection));
            if (aNetAssembly != null)
            {
                //Use the assembly in order to get the internal type for 
                // the internal class
                Type aSettingsType = aNetAssembly.GetType("System.Net.Configuration.SettingsSectionInternal");
                if (aSettingsType != null)
                {
                    //Use the internal static property to get an instance 
                    // of the internal settings class. If the static instance 
                    // isn't created allready the property will create it for us.
                    object anInstance = aSettingsType.InvokeMember("Section",
                    BindingFlags.Static | BindingFlags.GetProperty
                    | BindingFlags.NonPublic, null, null, new object[] { });
                    if (anInstance != null)
                    {
                        //Locate the private bool field that tells the 
                        // framework is unsafe header parsing should be 
                        // allowed or not
                        FieldInfo aUseUnsafeHeaderParsing = aSettingsType.GetField(
                        "useUnsafeHeaderParsing",
                        BindingFlags.NonPublic | BindingFlags.Instance);
                        if (aUseUnsafeHeaderParsing != null)
                            return (bool)aUseUnsafeHeaderParsing.GetValue(anInstance);
                    }
                }
            }
            return false;
        }
        void SetAllowUnsafeHeaderParsing(bool val)
        {
            //Get the assembly that contains the internal class
            Assembly aNetAssembly = Assembly.GetAssembly(typeof(System.Net.Configuration.SettingsSection));
            if (aNetAssembly != null)
            {
                //Use the assembly in order to get the internal type for 
                // the internal class
                Type aSettingsType = aNetAssembly.GetType("System.Net.Configuration.SettingsSectionInternal");
                if (aSettingsType != null)
                {
                    //Use the internal static property to get an instance 
                    // of the internal settings class. If the static instance 
                    // isn't created allready the property will create it for us.
                    object anInstance = aSettingsType.InvokeMember("Section",
                    BindingFlags.Static | BindingFlags.GetProperty
                    | BindingFlags.NonPublic, null, null, new object[] { });
                    if (anInstance != null)
                    {
                        //Locate the private bool field that tells the 
                        // framework is unsafe header parsing should be 
                        // allowed or not
                        FieldInfo aUseUnsafeHeaderParsing = aSettingsType.GetField(
                        "useUnsafeHeaderParsing",
                        BindingFlags.NonPublic | BindingFlags.Instance);
                        if (aUseUnsafeHeaderParsing != null)
                        {
                            aUseUnsafeHeaderParsing.SetValue(anInstance, val);
                        }
                    }
                }
            }
        }