Post 方式 模仿 form表单 上传 图片 设置enctype = multipart/form-data

<form  enctype="multipart/form-data"></form>

自定义 MultipartFormData 类  （4.5以上版本好像有这个类  类名称叫啥忘记了）

/// <summary>/// multipart/form-data 数据类型/// </summary>public class MultipartFormData{public static string ContentType = "multipart/form-data; boundary=A300x";private string headerStream = "--A300x\r\nContent-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: application/octet-stream\r\n\r\n";private string footerString = "--A300x--\r\n";private string compart = "\r\n";private string headerString = "--A300x\r\nContent-Disposition: form-data; name=\"{0}\"\r\n\r\n";private List<byte> lists = new List<byte>();private byte[] footerBytes;private byte[] comparts;public MultipartFormData(){footerBytes = Encoding.UTF8.GetBytes(footerString);comparts = Encoding.UTF8.GetBytes(compart);           }public byte[] Buffer{get{return lists.ToArray();}}private bool IsEnd = false;/// <summary>////// </summary>public void End(){if (!IsEnd){IsEnd = true;//lists.AddRange(footerBytes.ToList());   this.AddRanges(footerBytes);}}public void AddRanges(byte[] array) {foreach (byte b in array)lists.Add(b);}/// <summary>/// 向序列化到多部/窗体数据 MIME 类型的 对象集合添加 HTTP 内容/// </summary>/// <param name="content">要添加到集合中的 HTTP 内容</param>/// <param name="name">要添加的 HTTP 内容的名称</param>public void Add(string content, string name){byte[] headerBytes = Encoding.UTF8.GetBytes(String.Format(headerString, name));this.AddRanges(headerBytes);byte[] buffer = Encoding.UTF8.GetBytes(content);this.AddRanges(buffer);this.AddRanges(comparts);}/// <summary>/// 向序列化到多部/窗体数据 MIME 类型的 对象集合添加 HTTP 内容/// </summary>/// <param name="content">要添加到集合中的 HTTP 内容</param>/// <param name="name">要添加的 HTTP 内容的名称</param>/// <param name="fileName">要添加到集合中的 HTTP 内容的文件名</param>public void Add(Stream content, string name, string fileName){byte[] headerBytes = Encoding.UTF8.GetBytes(String.Format(headerStream, name, fileName));this.AddRanges(headerBytes);byte[] buffer = new byte[content.Length];content.Read(buffer, 0, buffer.Length);content.Seek(0, SeekOrigin.Begin);this.AddRanges(buffer);this.AddRanges(comparts);}/// <summary>/// 向序列化到多部/窗体数据 MIME 类型的 对象集合添加 HTTP 内容/// </summary>/// <param name="content">要添加到集合中的 HTTP 内容</param>/// <param name="name">要添加的 HTTP 内容的名称</param>/// <param name="fileName">要添加到集合中的 HTTP 内容的文件名</param>public void Add(byte[] content, string name, string fileName){byte[] headerBytes = Encoding.UTF8.GetBytes(String.Format(headerStream, name, fileName));this.AddRanges(headerBytes);this.AddRanges(content);this.AddRanges(comparts);}}

上传图片代码

        /// <summary>/// form-data 数据类型传递数据/// </summary>private MultipartFormData multiparFormData = new MultipartFormData();/// <summary>/// 键值对应/// </summary>/// <param name="key"></param>/// <param name="value"></param>public void AddFormData(string key, string value){this.multiparFormData.Add(value, key);}/// <summary>/// 传递一个 strem 类型/// </summary>/// <param name="key"></param>/// <param name="value"></param>/// <param name="fileName"></param>public void AddFormData(string key, Stream value, string fileName){this.multiparFormData.Add(value, key, fileName);}/// <summary>/// 传递一个 byte[] 类型/// </summary>/// <param name="key"></param>/// <param name="value"></param>/// <param name="fileName"></param>public void AddFormData(string key, byte[] value, string fileName){this.multiparFormData.Add(value, key, fileName);}private static CookieContainer m_Cookie = new CookieContainer();/// <summary>/// POST form-data 方式请求消息/// </summary>/// <param name="url"></param>/// <param name="isHttps"></param>/// <returns></returns>public string PostFromData(string url, bool isHttps) {try{multiparFormData.End();HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);request.Method = "POST";request.ContentType = MultipartFormData.ContentType;request.CookieContainer = m_Cookie;//设置上一个访问页面的cookie 保持sessionrequest.ContentLength = multiparFormData.Buffer.Length;Stream stream = request.GetRequestStream();stream.Write(multiparFormData.Buffer, 0, multiparFormData.Buffer.Length);stream.Close();WebResponse response = request.GetResponse();Stream streamResponse = response.GetResponseStream();StreamReader sr = new StreamReader(streamResponse);return sr.ReadToEnd();}catch (Exception ex) {Log.WriteLog("POST form-data 方式请求消息:" + ex.Message);return "error";}}