C# 实现文件与信息同步上传到服务器教程

public static class FormUpload
    {
        /// <summary>
        /// 字符编码格式
        /// </summary>
        private static readonly Encoding encoding = Encoding.UTF8;
        private const string DefaultUserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";

        /// <summary>
        /// 上传图像和参数
        /// </summary>
        /// <param name="url">上传地址</param>
        /// <param name="image">图像byte数组</param>
        /// <param name="imageName">图像名称，带扩展名</param>
        /// <param name="data">参数</param>
        /// <returns>响应内容</returns>
        public static string UploadImageAndData(string url,byte[] image,string imageName,Dictionary<string,string> datas)
        {
            Dictionary<string, object> dic = new Dictionary<string, object>();
            dic.Add("image1", new FormUpload.FileParameter(image, imageName));

            //
            foreach (KeyValuePair<string, string> keyValuePair in datas)
            {
                dic.Add(keyValuePair.Key, keyValuePair.Value);
            }

            try
            {
                HttpWebResponse r = FormUpload.MultipartFormDataPost(url, DefaultUserAgent, dic);

                Stream instream = r.GetResponseStream();
                StreamReader sr = new StreamReader(instream, Encoding.UTF8);
                //返回结果网页(html)代码 
                string retValue = sr.ReadToEnd();
                sr.Close();
                return retValue;
            }
            catch (Exception)
            {

                throw;
            }
        }

        public static HttpWebResponse MultipartFormDataPost(string postUrl, string userAgent, Dictionary<string, object> postParameters)
        {
            //分割标记
            string formDataBoundary = String.Format("----------{0:N}", Guid.NewGuid());
            //内容类型
            string contentType = "multipart/form-data; boundary=" + formDataBoundary;
            byte[] formData = GetMultipartFormData(postParameters, formDataBoundary);
            return PostForm(postUrl, userAgent, contentType, formData);
        }

        private static HttpWebResponse PostForm(string postUrl, string userAgent, string contentType, byte[] formData)
        {
            HttpWebRequest request = WebRequest.Create(postUrl) as HttpWebRequest;
            if (request == null)
            {
                throw new NullReferenceException("request is not a http request");