C# P2P通信之UPNP操作类的实现

主要依托于COM互操作来实现

添加COM引用 使用UPNP 1.0类型库 npnp.dll

主要对UPNP操作做了一个封装

1.自定义类型支持

 

public   enum  ProtocolType
{
    UDP,
    TCP
}

///   <summary>
///  端口映射信息
///   </summary>
public   class  PortMappingInfo
{
     public   string  InternalIP;
     public   int  ExternalPort;
     public   int  InternalPort;
     public  ProtocolType type;
     public   string  Description;
     public  PortMappingInfo( string  internalIP,  int  externalPort,  int  internalPort, ProtocolType type,  string  description)
    {
         this .InternalIP  =  internalIP;
         this .ExternalPort  =  externalPort;
         this .InternalPort  =  internalPort;
         this .type  =  type;
         this .Description  =  description;
    }
}

 

2.UPnP类实现

 

using  System;
using  System.Collections.Generic;
using  System.Collections;
using  System.Text;
using  System.Net;
using  System.Xml;
using  System.IO;
using  System.Net.Sockets;
using  NATUPNPLib;

namespace  Network
{
     public   sealed   class  UPnPNat
    {
         private  UPnPNATClass _uPnPNAT;
        
         public  UPnPNat()
        {
             try
            {
                UPnPNATClass nat  =   new  UPnPNATClass();
                 // if (nat.NATEventManager != null && nat.StaticPortMappingCollection != null)
                    _uPnPNAT  =  nat;
            }
             catch {}

             if (_uPnPNAT == null )
                 throw   new  NotSupportedException( " 没有可配置的UPNP NAT活动 " );
        }
         ///   <summary>
         ///  增加端口映射
         ///   </summary>
         ///   <param name="ExternalPort"> 外部端口（路由器 NAT设备打开的端口） </param>
         ///   <param name="InternalPort"> 内部端口 本机的端口 </param>
         ///   <param name="type"> 协议类型 UDP或TCP </param>
         ///   <param name="InternalClient"> 内网IP地址或主机名 </param>
         ///   <param name="enable"> 是否启用 </param>
         ///   <param name="description"> 描述信息 </param>
         public   void  AddStaticPortMapping( int  ExternalPort, int  InternalPort,ProtocolType type, string  InternalClient, bool  enable, string  description)
        {
            _uPnPNAT.StaticPortMappingCollection.Add(ExternalPort, type.ToString().ToUpper(), InternalPort, InternalClient, enable, description);
        }
         ///   <summary>
         ///  移除端口映射
         ///   </summary>
         ///   <param name="ExternalPort"> 外部端口号 </param>
         ///   <param name="type"> 协议类型 </param>
         public   void  RemoveStaticPortMapping( int  ExternalPort,ProtocolType type)
        {
            _uPnPNAT.StaticPortMappingCollection.Remove(ExternalPort, type.ToString().ToUpper());
        }
         public  UPnPNATClass UPnPNAT
        {
             get  {  return  _uPnPNAT; }
        }

         ///   <summary>
         ///  获取端口映射信息
         ///   </summary>
         public  PortMappingInfo[] PortMappingsInfos
        {
             get
            {
                System.Collections.ArrayList portMappings  =   new  ArrayList();
                 int  count  =  _uPnPNAT.StaticPortMappingCollection.Count;
                IEnumerator enumerator  =  _uPnPNAT.StaticPortMappingCollection.GetEnumerator();
                enumerator.Reset();
                 for  ( int  i  =   0 ; i  <  count; i ++ )
                {
                    IStaticPortMapping mapping  =   null ;
                     try
                    {
                         if (enumerator.MoveNext())
                            mapping = (IStaticPortMapping)enumerator.Current;
                    }
                     catch  { }
                     if  (mapping  !=   null )
                        portMappings.Add( new  PortMappingInfo(mapping.InternalClient, mapping.ExternalPort, mapping.InternalPort, mapping.Protocol  ==   " TCP "   ?  ProtocolType.TCP : ProtocolType.UDP, mapping.Description));
                }
                PortMappingInfo[] portMappingInfos  =   new  PortMappingInfo[portMappings.Count];
                portMappings.CopyTo(portMappingInfos);
                 return  portMappingInfos;
            }
        }
        
    }

    
}

 

使用NAT设备（路由器）的端口映射功能是实现P2P的一种重要方式 在UPNP开启的情况下把一台内网计算机直接暴露到公网上