C# 最齐全的上传图片方法

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考高分网！