.NET HttpPost 上传文件图片到服务器

 public class ImageData
    {
        public string imageFilePath { get; set; }
        public string tempFilePath { get; set; }
    }

        ImageData data = new ImageData();
        [HttpPost]
        public ImageData UploadFile()
        {
            HttpContext context = HttpContext.Current;
            if (context.Request.Files.Count == 0)//判断文件是否存在
                return null;
            String outFilePath = context.Server.MapPath("~/ImageFile/");
            string time = System.DateTime.Now.ToFileTimeUtc().ToString() + "/";
            System.IO.Directory.CreateDirectory(outFilePath + time);
            string imageFilePath = outFilePath + time + context.Request.Files[0].FileName;
            context.Request.Files[0].SaveAs(imageFilePath);
            string thumbnailFilePath = outFilePath + time + "temp_" + context.Request.Files[0].FileName;
            getImage(imageFilePath, 60, 2, thumbnailFilePath);

            data.imageFilePath = "localhost:12380/ImageFile/" + time + context.Request.Files[0].FileName;
            data.tempFilePath = "localhost:12380/ImageFile/" + time + "temp_" + context.Request.Files[0].FileName;
            return data;
        }

        /// <summary>
        /// 生成缩略图
        /// </summary>
        /// <param name="sourceFile">原始图片文件</param>
        /// <param name="quality">质量压缩比</param>
        /// <param name="multiple">收缩倍数</param>
        /// <param name="outputFile">输出文件名</param>
        /// <returns>成功返回true,失败则返回false</returns>
        public static bool getImage(String sourceFile, long quality, int multiple, String outputFile)
        {
            try
            {
                long imageQuality = quality;
                Bitmap sourceImage = new Bitmap(sourceFile);
                ImageCodecInfo myImageCodecInfo = GetEncoderInfo("image/jpeg");
                System.Drawing.Imaging.Encoder myEncoder = System.Drawing.Imaging.Encoder.Quality;
                EncoderParameters myEncoderParameters = new EncoderParameters(1);
                EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, imageQuality);
                myEncoderParameters.Param[0] = myEncoderParameter;
                float xWidth = sourceImage.Width;
                float yWidth = sourceImage.Height;
                Bitmap newImage = new Bitmap((int)(xWidth / multiple), (int)(yWidth / multiple));
                Graphics g = Graphics.FromImage(newImage);

                g.DrawImage(sourceImage, 0, 0, xWidth / multiple, yWidth / multiple);
                g.Dispose();
                newImage.Save(outputFile, myImageCodecInfo, myEncoderParameters);
                return true;
            }
            catch
            {
                return false;
            }
        }

        /// <summary>
        /// 获取图片编码信息
        /// </summary>
        private static ImageCodecInfo GetEncoderInfo(String mimeType)
        {
            int j;
            ImageCodecInfo[] encoders;
            encoders = ImageCodecInfo.GetImageEncoders();
            for (j = 0; j < encoders.Length; ++j)
            {
                if (encoders[j].MimeType == mimeType)
                    return encoders[j];
            }

            return null;
        }

原文地址：https://www.cnblogs.com/Warmsunshine/p/9853708.html