System.Net.HttpWebRequest
                req = System.Net.HttpWebRequest.Create("http://192.168.186.94/fortest.ashx") as System.Net.HttpWebRequest;
            req.Method = System.Net.WebRequestMethods.Http.Post;

            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            using (System.IO.FileStream fs = new System.IO.FileStream(@"XXX", System.IO.FileMode.Open))
            {
                Int32 by = -1;
                while ((by = fs.ReadByte()) != -1)
                {
                    ms.WriteByte((Byte)by);
                }
            }
            Byte[] buffer = ms.ToArray();
            req.ContentLength = buffer.Length;

            req.ContentType = "application/x-www-form-urlencoded";

            req.Headers.Add("UserName", "mgsg");
            req.Headers.Add("Pwd", "123456789");
            req.Headers.Add("FileName", "yiyuan.emr");
            req.Headers.Add("Kind", "zhongyi");
            req.Headers.Add("Field", "jilu");

            System.IO.Stream str = req.GetRequestStream();
            str.Write(buffer, 0, buffer.Length);

            System.Net.HttpWebResponse response = req.GetResponse() as System.Net.HttpWebResponse;
            if (response.StatusCode == System.Net.HttpStatusCode.OK)
            {
                using (System.IO.StreamReader
                    sr = new System.IO.StreamReader(response.GetResponseStream(), Encoding.GetEncoding("gb2312")))
                {
                    Console.Write(sr.ReadToEnd());
                }
            }
            else
                Console.WriteLine(response.StatusCode);

HttpPostedFile upFile = up_file.PostedFile;//HttpPostedFile对象,用来读取上传图片的属性
            fileLength = upFile.ContentLength;//记录文件的长度
   try
   {
    if(fileLength==0)//当文件长度为0的时候
    {
     txtMessage.Text = "请选择要上传的文件!";
    }
    else
    {
     byte[] fileByte = new byte[fileLength];//用图片的长度来初始化一个字节数组存储临时的图片文件
     Stream fileStream = upFile.InputStream;//建立文件流对象
     fileStream.Read(fileByte,0,fileLength);//读取图片数据到临时存储体fileByte,0为数据指针位置,fileLength为数据长度
     string connString = "Data Source=192.168.1.250;database=image;uid=pwqzc;pwd=cn0088";
     SqlConnection conn = new SqlConnection(connString);//初始化数据库连接
     string insertStr = "insert into image (image_data,image_content_type,image_description,image_size) values (@image_data,@image_content_type,@image_description,@image_size)";
     //插入数据库语句
     SqlCommand comm = new SqlCommand(insertStr,conn);
     comm.Parameters.Add(new SqlParameter("@image_data",SqlDbType.Image));//添加参数
     comm.Parameters["@image_data"].Value = fileByte;//给参数赋值
     comm.Parameters.Add(new SqlParameter("@image_content_type",SqlDbType.VarChar,50));
     comm.Parameters["@image_content_type"].Value = upFile.ContentType;//记录图片类型
     comm.Parameters.Add(new SqlParameter("@image_description",SqlDbType.VarChar,50));
     comm.Parameters["@image_description"].Value = txtDescription.Text;//把其他的表单数据上传
     comm.Parameters.Add(new SqlParameter("@image_size",SqlDbType.Int,4));
     comm.Parameters["@image_size"].Value = upFile.ContentLength;//记录图片长度,读取数据的时候使用
     conn.Open();//打开数据库连接
     comm.ExecuteNonQuery();//添加数据
     conn.Close();//关闭数据库
     txtMessage.Text = "你已经成功的上传了图片";
    }
   }
   catch(Exception ex)
   {
       txtMessage.Text = ex.Message.ToString();
   }
  }
 }