无法将上传的图像转换为字节数组
unable to convert uploaded image to byte array
我正在尝试将上传的图像转换为字节数组,以便将其存储在数据库中 table。
下面的代码用于执行从图像到字节数组的转换:
public byte[] ConvertToBytes(HttpPostedFileBase image)
{
BinaryReader reader = new BinaryReader(image.InputStream);
var imageBytes = reader.ReadBytes((int)image.ContentLength);
return imageBytes;
}
当我在此代码上放置断点以查看返回的内容时,imageBytes 变量显示 {byte[0]}。
下面显示的代码是我用来上传此图片的视图的控制器中的接收 ActionResult(目前我正在使用文件输入 select 并上传图片):
[HttpPost]
public ActionResult NewsManager(NewsManagerViewModel model)
{
var newsManagerRepository = new NewsManagerRepository();
var currentUser = User.Identity.Name;
if (ModelState.IsValid)
{
HttpPostedFileBase file = Request.Files["ImageData"];
var fileIsImage = file.IsImage();
if (fileIsImage)
{
model.Author = currentUser;
var newsUploaded = newsManagerRepository.UploadNews(file, model);
if (newsUploaded == 1)
{
return View();
}
ModelState.AddModelError("uploadFailed", "News item was not uploaded");
return View(model);
}
ModelState.AddModelError("fileNotImage", "the file you have uploaded is not an image");
return View(model);
}
return View(model);
}
有人知道为什么我正在转换的图像没有成功转换为字节数组吗?
任何建议将不胜感激,该应用程序目前是 MVC 5 和 .net 4.5 版。
调用方法代码如下:
public int UploadNews(HttpPostedFileBase file, NewsManagerViewModel model)
{
model.BannerImage = ConvertToBytes(file);
var ndtms2Utils = new NDTMS2UtilsEntities();
var news = new News
{
Title = model.Title,
Author = model.Author,
BannerImage = model.BannerImage,
DateCreated = DateTime.Now,
NewsContent = model.NewsContent
};
ndtms2Utils.News.Add(news);
int i = ndtms2Utils.SaveChanges();
if (i == 1)
{
return 1;
}
return 0;
}
使用下面提到的转换方法:
public byte[] ConvertToBytes(HttpPostedFileBase image)
{
return image.InputStream.StreamToByteArray();
}
public static byte[] StreamToByteArray(this Stream input)
{
input.Position = 0;
using (var ms = new MemoryStream())
{
int length = System.Convert.ToInt32(input.Length);
input.CopyTo(ms, length);
return ms.ToArray();
}
}
我正在尝试将上传的图像转换为字节数组,以便将其存储在数据库中 table。
下面的代码用于执行从图像到字节数组的转换:
public byte[] ConvertToBytes(HttpPostedFileBase image)
{
BinaryReader reader = new BinaryReader(image.InputStream);
var imageBytes = reader.ReadBytes((int)image.ContentLength);
return imageBytes;
}
当我在此代码上放置断点以查看返回的内容时,imageBytes 变量显示 {byte[0]}。
下面显示的代码是我用来上传此图片的视图的控制器中的接收 ActionResult(目前我正在使用文件输入 select 并上传图片):
[HttpPost]
public ActionResult NewsManager(NewsManagerViewModel model)
{
var newsManagerRepository = new NewsManagerRepository();
var currentUser = User.Identity.Name;
if (ModelState.IsValid)
{
HttpPostedFileBase file = Request.Files["ImageData"];
var fileIsImage = file.IsImage();
if (fileIsImage)
{
model.Author = currentUser;
var newsUploaded = newsManagerRepository.UploadNews(file, model);
if (newsUploaded == 1)
{
return View();
}
ModelState.AddModelError("uploadFailed", "News item was not uploaded");
return View(model);
}
ModelState.AddModelError("fileNotImage", "the file you have uploaded is not an image");
return View(model);
}
return View(model);
}
有人知道为什么我正在转换的图像没有成功转换为字节数组吗?
任何建议将不胜感激,该应用程序目前是 MVC 5 和 .net 4.5 版。
调用方法代码如下:
public int UploadNews(HttpPostedFileBase file, NewsManagerViewModel model)
{
model.BannerImage = ConvertToBytes(file);
var ndtms2Utils = new NDTMS2UtilsEntities();
var news = new News
{
Title = model.Title,
Author = model.Author,
BannerImage = model.BannerImage,
DateCreated = DateTime.Now,
NewsContent = model.NewsContent
};
ndtms2Utils.News.Add(news);
int i = ndtms2Utils.SaveChanges();
if (i == 1)
{
return 1;
}
return 0;
}
使用下面提到的转换方法:
public byte[] ConvertToBytes(HttpPostedFileBase image)
{
return image.InputStream.StreamToByteArray();
}
public static byte[] StreamToByteArray(this Stream input)
{
input.Position = 0;
using (var ms = new MemoryStream())
{
int length = System.Convert.ToInt32(input.Length);
input.CopyTo(ms, length);
return ms.ToArray();
}
}