图片上传根据stream生成image

                public
                class
                 UploadService
{    
    
                public
                bool SaveAs(UploadRequest request, outstring filePath, outstring errMessage)
        {
            filePath = string.Empty;

            //**************************************初始化byte长度.byte[] file = new Byte[request.PostedFile.ContentLength];
            //**************************************读取stream，并转换为byte类型以及获取image类型
            System.IO.Stream stream = request.PostedFile.InputStream;
            stream.Read(file, 0, request.PostedFile.ContentLength);
            Image image = System.Drawing.Image.FromStream(stream);
            stream.Close();
            //**************************************判断条件if(!CheckFile(request,image, file, out errMessage)){
                returnfalse;
            }
            //**************************************设置路径
            SetFile(ref request);
            filePath = request.SavePath;
            //**************************************保存至文件路径var fs = new FileStream(filePath, FileMode.Create, FileAccess.Write);
            fs.Write(file, 0, file.Length);
            fs.Flush();
            fs.Close();

            //**************************************获取相对路径
            filePath = GetSimplePath(filePath);
            if (string.IsNullOrEmpty(errMessage))
            {
                returntrue;
            }
            else
            {
                returnfalse;
            }
        }

        ///<summary>/// 判断文件的相关条件
        ///</summary>///<param name="request"></param>///<param name="file"></param>///<param name="errMessage"></param>///<returns></returns>privatebool CheckFile(UploadRequest request,Image image, byte[] file, outstring errMessage)
        {
            errMessage = string.Empty;
            // 读取原始文件名string localFileName = Path.GetFileName(request.PostedFile.FileName);

            //得到扩展名var ext = localFileName.Substring(localFileName.LastIndexOf(‘.‘) + 1).ToLower();
            //如果没有设定扩展名，则使用本身的扩展名存储if (string.IsNullOrEmpty(request.Ext))
            {
                request.Ext = ext;
            }
            //判断传入的数据if (file.Length == 0)
            {
                errMessage = "无数据提交";
                returnfalse;
            }
            //判断文件是否超过限定大小if (file.Length > this.MaxFilesize)
            {
                errMessage = "文件大小超过" + this.MaxFilesize + "字节";
                returnfalse;
            }
            //判断扩展名是否属于给定的if (request.Format!=null&& request.Format.Length > 0 && !request.Format.Contains(ext))
            {
                errMessage = "上传文件扩展名必需为：" + string.Join(",", request.Format);
                returnfalse;
            }
            //判断宽高是否符合要求if (request.Width > 0||request.Height>0)
            {
                if (request.Width>0&&Math.Abs( image.Width-request.Width)>1)
                {
                    errMessage="宽不符合";
                    image.Dispose();
                    returnfalse;
                }
                elseif(request.Height>0&&Math.Abs(image.Height-request.Height)>1){
                    errMessage="高不符合";
                    image.Dispose();
                    returnfalse;
                }
            }
            returntrue;
        }

        ///<summary>/// 设置保存路径以及创建文件夹
        ///</summary>///<param name="request"></param>privatevoid SetFile(ref UploadRequest request)
        {
            //如果路径没有设定，则按照给定的路径设置，不过给定路径的话，一定得先确保这个路径是正确的，且存在的if (string.IsNullOrEmpty(request.SavePath))
            {
                string subfolder = "day_" + DateTime.Now.ToString("yyMMdd");
                string fileFolder = Path.Combine(UploadConfigContext.UploadPath, request.Folder, subfolder);
                //文件全路径
                request.SavePath = Path.Combine(fileFolder,
                    string.Format("{0}{1}.{2}", DateTime.Now.ToString("yyyyMMddhhmmss"),
                    new Random(DateTime.Now.Millisecond).Next(10000), request.Ext)
                );
                if (!Directory.Exists(fileFolder))
                {
                    Directory.CreateDirectory(fileFolder);
                }
            }
        }
    }

    ///<summary>/// 上传使用的参数
    ///</summary>publicclass UploadRequest
    {
        ///<summary>/// 自行设置时，保存的子文件夹
        ///</summary>publicstring Folder { get; set; }
        ///<summary>/// 设置路径的，如果没设置，则代码自行设置
        ///</summary>publicstring SavePath { get; set; }
        ///<summary>/// 上传的数据
        ///</summary>public HttpPostedFileBase PostedFile { get; set; }
        ///<summary>/// 用来自定义控制扩展名的
        ///</summary>publicstring[] Format { get; set; }

        ///<summary>/// 控制宽，<=0则表示不管
///</summary>publicint Width { get; set; }
        ///<summary>/// 控制高，<=0则表示不管
///</summary>publicint Height { get; set; }

        ///<summary>/// 扩展名
        ///</summary>publicstring Ext { get; set; }
    }