asp.net-mvc-3 - 如何在MVC3中限制FileUpload中的文件类型？

Question

我有一个文件上传功能，用户可以上传文件。我想限制用户上传某些文件类型。允许的类型是: .doc、.xlsx、.txt、.jpeg .

我怎么能做到这一点？

这是我的实际文件上传代码:

      public ActionResult UploadFile(string AttachmentName, BugModel model)
       {            
        BugModel bug = null;
        if (Session["CaptureData"] == null)
        {
            bug = model;
        }
        else
        {
            bug = (BugModel)Session["CaptureData"];
        }
        foreach (string inputTagName in Request.Files)
        {
            HttpPostedFileBase file1 = Request.Files[inputTagName];
            if (file1.ContentLength > 0)
            {
                string path = "/Content/UploadedFiles/" + Path.GetFileName(file1.FileName);
                string savedFileName = Path.Combine(Server.MapPath("~" + path));
                file1.SaveAs(savedFileName);
                BugAttachment attachment = new BugAttachment();
                attachment.FileName = "~" + path.ToString();
                attachment.AttachmentName = AttachmentName;
                attachment.AttachmentUrl = attachment.FileName;
                bug.ListFile.Add(attachment);
                model = bug;
                Session["CaptureData"] = model;
            }
        }
        ModelState.Clear();
        return View("LoadBug", bug);
    }

Answer 1

首先要验证的是file1.FileName中包含的文件扩展名是否匹配允许的扩展名之一。然后，如果您真的想确保用户没有将其他文件类型重命名为允许的扩展名，则需要查看文件的内容以识别它是否是允许的类型之一。

以下是如何检查文件扩展名是否属于预定义扩展名列表的示例:

var allowedExtensions = new[] { ".doc", ".xlsx", ".txt", ".jpeg" };
var extension = Path.GetExtension(file1.FileName);
if (!allowedExtensions.Contains(extension))
{
    // Not allowed
}