上传jpg格式图片为什么上传不上去？？？？

[hdf336]

if (FileUpload1.PostedFile.ContentType.Equals(System.Drawing.Imaging.ImageFormat.Jpeg))
{

string filename = FileUpload1.FileName;

string file = filename.Substring(filename.LastIndexOf("\\") + 1);

FileUpload1.SaveAs(Server.MapPath("uploads/" + file));
}
else
Response.Write("<script>alert('上传格式不支持！');</script>");

[liyong11111]

protected void btnupload_Click(object sender, EventArgs e)
    {
        Boolean fileOK = false;
        String path = Server.MapPath("~/UploadFiles/");
        if (fuupload.HasFile)
        {
            String fileExtension = System.IO.Path.GetExtension(fuupload.FileName).ToLower();
            String[] allowedExtensions = { ".txt", ".doc", ".xml", ".jpg",".exe" };
            for (int i = 0; i < allowedExtensions.Length; i++)
            {
                if (fileExtension == allowedExtensions[i])
                {
                    fileOK = true;
                }
            }
        }

        //如果文件类型符合
        if (fileOK)
        {
            try
            {
                // 将文件保存到指定的文件夹下
                fuupload.PostedFile.SaveAs(path + fuupload.FileName);
                labmsg.Text = "File Upload Succeed!";
            }
            catch
            {
                labmsg.Text = "Upload Fail!";
            }
        }
        else
        {
            labmsg.Text = "File Type or Size is Unallowed!";
        }

    }

[zpcoder]

你应该说说是怎么上传不上去法,你是不是上错了地方，看清楚路径：FileUpload1.SaveAs(Server.MapPath("uploads/" + file));

[「已注销」]

//上传新的文件
int i = 1000;//允许上传文件大小的最大值,单位为KB
string[] arrExtension = { ".gif", ".jpg", ".jpeg", ".bmp", ".png" };
if (File1.PostedFile.FileName != string.Empty)
{
if ((IsAllowedLength(File1, i)) && (IsAllowedExtension(File1, arrExtension)))
{
//删除旧的文件
string strAbsolutePath = Server.MapPath("~/Teacher/");

_Teacher.TeacherPic = SaveFile(File1, strAbsolutePath);
}
else
{
Response.Write("<script>alert('上传的不是图片文件或者图片大小已经超过1M !');</script>");
}
}

[hdf336]

找了下原因，这样才正确（上传jpg格式文件）

if (FileUpload1.PostedFile.ContentType.ToString().ToLower().Equals("image/pjpeg"))
{
string filename = FileUpload1.FileName;
string file = filename.Substring(filename.LastIndexOf("\\") + 1);
FileUpload1.SaveAs(Server.MapPath("uploads/" + file));
}
else
Response.Write("<script>alert('上传格式不支持！');</script>");