使用C#調用Java帶MIME附件WebService方法的初步設想

    朋友說開發電信的MMS，其實需要圖片作為附件放在調用WebService介面上，使用Http的Content-Type: Multipart/Related;來發送，真讓人感覺不倫不類的。不知道為什麼不設計成一個欄位是BASE64編碼得了唄。

    難道只能用朋友說的拼欄位的方法了不？ 我用Reflect分析了一下，貌似這樣也可以實現。

    我們知道，我們添加一個WebService引用時，會自動產生從  SoapHttpClientProtocol 的子類。我的想法是，我們寫一個 繼承自"SoapHttpClientProtocol” 的子類SoapHttpClientProtocolEX, 重寫方法：GetWebRequest() 返回我們寫的代碼 HttpWebRequestEx類，然後在原始 HttpWebRequest 類的GetRequestStream()時，返回我們的流轉移器：NetwordStreamEx ，並在方法關閉流 Close() 前，加入自訂的附件資訊。

    不知道說清楚沒有， 這裡列了部分代碼架構：

 

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Web.Services.Protocols;using System.Net;using System.Net.Sockets;using System.IO;namespace Foundway.Util.WebService{    public class SoapHttpClientProtocolEx : SoapHttpClientProtocol    {        private List<string> attachments = new List<string>();        /// <summary>        /// 添加一個附件        /// </summary>        /// <param name="attachment">附件全路徑</param>        public void AddAttachment(string attachment)        {            attachments.Add(attachment);        }        protected override  WebRequest GetWebRequest(Uri uri)        {            WebRequest request =   base.GetWebRequest(uri);            if (attachments.Count > 0)            {                HttpWebRequest httpRequest = request as HttpWebRequest;                if (httpRequest != null)                {                    httpRequest.SendChunked = true; //使用多段發送                    HttpWebRequestEx httpRequestEx = new HttpWebRequestEx(httpRequest, attachments.ToArray());                    return httpRequestEx;                }            }            return request;        }    }    public class HttpWebRequestEx : WebRequest    {        private string[] attachments;        private HttpWebRequest httpRequest = null;        public HttpWebRequestEx(HttpWebRequest httpRequest, string[] attachments)        {            this.httpRequest = httpRequest;            this.attachments = attachments;        }        public override System.IO.Stream GetRequestStream()        {            Stream stream = httpRequest.GetRequestStream();            //返回自訂的流代理，來完成附件的資訊            return new NetworkStreamEx(stream, this.attachments);        }        #region 重寫其它全部公用方法        public override void Abort()        {            httpRequest.Abort();        }        public override IAsyncResult BeginGetRequestStream(AsyncCallback callback, object state)        {            return httpRequest.BeginGetRequestStream(callback, state);        }        public override IAsyncResult BeginGetResponse(AsyncCallback callback, object state)        {            return httpRequest.BeginGetResponse(callback, state);        }        public override System.Net.Cache.RequestCachePolicy CachePolicy        {            get            {                return httpRequest.CachePolicy;            }            set            {                httpRequest.CachePolicy = value;            }        }        public override string ConnectionGroupName        {            get            {                return httpRequest.ConnectionGroupName;            }            set            {                httpRequest.ConnectionGroupName = value;            }        }        public override long ContentLength        {            get            {                return httpRequest.ContentLength;            }            set            {                httpRequest.ContentLength = value;            }        }        public override string ContentType        {            get            {                return httpRequest.ContentType;            }            set            {                httpRequest.ContentType = value;            }        }        public override System.Runtime.Remoting.ObjRef CreateObjRef(Type requestedType)        {            return httpRequest.CreateObjRef(requestedType);        }        public override ICredentials Credentials        {            get            {                return httpRequest.Credentials;            }            set            {                httpRequest.Credentials = value;            }        }        public override Stream EndGetRequestStream(IAsyncResult asyncResult)        {            return httpRequest.EndGetRequestStream(asyncResult);        }        public override WebResponse EndGetResponse(IAsyncResult asyncResult)        {            return httpRequest.EndGetResponse(asyncResult);        }        public override WebResponse GetResponse()        {            return httpRequest.GetResponse();        }        public override WebHeaderCollection Headers        {            get            {                return httpRequest.Headers;            }            set            {                httpRequest.Headers = value;            }        }        public override string Method        {            get            {                return httpRequest.Method;            }            set            {                httpRequest.Method = value;            }        }        public override bool PreAuthenticate        {            get            {                return httpRequest.PreAuthenticate;            }            set            {                httpRequest.PreAuthenticate = value;            }        }        public override IWebProxy Proxy        {            get            {                return httpRequest.Proxy;            }            set            {                httpRequest.Proxy = value;            }        }        public override object InitializeLifetimeService()        {            return httpRequest.InitializeLifetimeService();        }        public override Uri RequestUri        {            get            {                return httpRequest.RequestUri;            }        }        public override int Timeout        {            get            {                return httpRequest.Timeout;            }            set            {                httpRequest.Timeout = value;            }        }        public override string ToString()        {            return httpRequest.ToString();        }        public override bool UseDefaultCredentials        {            get            {                return httpRequest.UseDefaultCredentials;            }            set            {                httpRequest.UseDefaultCredentials = value;            }        }        public override bool Equals(object obj)        {            return httpRequest.Equals(obj);        }        public override int GetHashCode()        {            return httpRequest.GetHashCode();        }        #endregion    }    public class NetworkStreamEx :Stream    {        private string[] attachments;        private Stream baseStream;                public NetworkStreamEx(Stream baseStream, string[] attachments)        {            this.baseStream = baseStream;        }        /// <summary>        /// 在關閉時，加入附件資訊        /// </summary>        public override void Close()        {            ///TODO:這裡添加附件資訊，            ///這裡就不加代碼了            ///            base.Close();        }        #region 把其它公用方法轉寄到原流        public override bool CanRead        {            get { return baseStream.CanRead; }        }        public override bool CanSeek        {            get { return baseStream.CanSeek; }        }        public override bool CanWrite        {            get { return baseStream.CanWrite; }        }        public override void Flush()        {            baseStream.Flush();        }        public override long Length        {            get { return baseStream.Length; }        }        public override long Position        {            get            {                return baseStream.Position;            }            set            {                baseStream.Position  = value;            }        }        public override int Read(byte[] buffer, int offset, int count)        {            return baseStream.Read(buffer, offset, count);        }        public override long Seek(long offset, SeekOrigin origin)        {            return baseStream.Seek(offset, origin);        }        public override void SetLength(long value)        {            baseStream.SetLength(value);        }        public override void Write(byte[] buffer, int offset, int count)        {            baseStream.Write(buffer, offset, count);        }        #endregion    }    }

引自：51aspx