方法里包括了图片大小限制、图片尺寸、文件内容等等的判断。。。

该案例是mvc下的demo，支持单张图片上传。

public ActionResult Upload() { string imgurl = ""; foreach (string key in Request.Files) { //这里只测试上传第一张图片file[0] HttpPostedFileBase file0 = Request.Files[key]; //转换成byte,读取图片MIME类型 Stream stream; int size = file0.ContentLength / 1024; //文件大小KB if (size > 1024) { return Content(ReturnMsg(Enum_Return.失败, "图片不能超过1M：", null)); } byte[] fileByte = new byte[2];//contentLength，这里我们只读取文件长度的前两位用于判断就好了，这样速度比较快，剩下的也用不到。 stream = file0.InputStream; stream.Read(fileByte, 0, 2);//contentLength，还是取前两位 //获取图片宽和高 //System.Drawing.Image image = System.Drawing.Image.FromStream(stream); //int width = image.Width; //int height = image.Height; string fileFlag = ""; if (fileByte != null && fileByte.Length > 0)//图片数据是否为空 { fileFlag = fileByte[0].ToString() fileByte[1].ToString(); } string[] fileTypeStr = { "255216", "7173", "6677", "13780" };//对应的图片格式jpg,gif,bmp,png if (fileTypeStr.Contains(fileFlag)) { string action = Request["action"]; string path = "/uploads/"; switch (action) { case "headimage": path = "headimage/"; break; case "blogtype": path = "blogtype/"; break; } string fullpath = path UserInfo.userID "/"; if (!Directory.Exists(Server.MapPath(fullpath))) { Directory.CreateDirectory(Server.MapPath(fullpath)); } Request.Files[key].SaveAs(Server.MapPath(fullpath Request.Files[key].FileName)); imgurl = fullpath Request.Files[key].FileName; } else { return Content(ReturnMsg(Enum_Return.失败, "图片格式不正确：" fileFlag, null)); } stream.Close(); } return Content(ReturnMsg(Enum_Return.成功, "上传成功", imgurl)); }

一般处理程序

public void ProcessRequest(HttpContext context) { context.Response.ContentType = "application/json"; HttpPostedFile _upfile = context.Request.Files["File"]; if (_upfile.ContentLength < 500000) { if (string.IsNullOrEmpty(_upfile.FileName)) { context.Response.Write("请上传图片"); } string fileFullname = _upfile.FileName; string dataName = DateTime.Now.ToString("yyyyMMddhhmmss"); string fileName = fileFullname.Substring(fileFullname.LastIndexOf("\\") 1); string type = fileFullname.Substring(fileFullname.LastIndexOf(".") 1); if (type == "bmp" || type == "jpg" || type == "gif" || type == "JPG" || type == "BMP" || type == "GIF") { _upfile.SaveAs(HttpContext.Current.Server.MapPath("photo") "\\" dataName "." type); HttpCookie cookie = new HttpCookie("photo"); context.Response.Write("上传成功"); } else { context.Response.Write("支持格式：|jpg|gif|bmp|"); } } else { context.Response.Write("你的图片已经超过500K的大小！"); } }

以上就是本文的全部内容，希望本文的内容对大家的学习或者工作能带来一定的帮助，同时也希望多多支持！