图片上传控件

 ///<summary>
    /// 图片上传
    ///</summary>
    ///<returns></returns>
    private string Upload_Images()
    {
        Boolean fileOK = false;
        string imageFile = "";
        String path = Server.MapPath("~/images/");  //设置服务器上传的路径，即文件上传的位置
        if (fulImage.PostedFile.ContentLength / 1024 < 2000)
        {
            if (fulImage.HasFile)
            {
                //获取上传文件类型
                String fileExtension = System.IO.Path.GetExtension(fulImage.FileName).ToLower();
                //判断允许上传图片类型
                String[] allowedExtensions = { ".gif", ".png", ".jpeg", ".jpg" };
                for (int i = 0; i < allowedExtensions.Length; i++)
                {
                    if (fileExtension == allowedExtensions[i])
                    {
                        fileOK = true;
                        break;
                    }
                }
            }
            else if (!string.IsNullOrEmpty(this.imgPic.ImageUrl))
            {
                return imageFile = this.imgPic.ImageUrl;
            }

            if (fileOK)
            {
                try
                {
                    //把当前时间取出，组成字符串，加入文件名称，防止重复命名
                    string fileName = DateTime.Now.ToString().Replace("-", "").Replace("", "").Replace(":", "") + fulImage.FileName;
                    fulImage.PostedFile.SaveAs(path + fileName);
                    imageFile = "../Images/" + fileName;
                }
                catch (Exception)
                {
                    Response.Write("<script>alert('对不起，图片不能上传！')</script>");
                }
            }
            else
            {
                if (string.IsNullOrEmpty(Request["newsId"]))//如果是新增显示提示，修改不显示提示
                    Response.Write("<script>alert('对不起，不能接受这种文件类型！')</script>");
            }
        }
        else
        {
            Response.Write("<script>alert('对不起，图片过大不能上传！')</script>");
        }
        return imageFile;
    }