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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));
}
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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！");
}
}
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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！
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