FileUpload 过滤设置

Question

说明：
WEB 页面上有一FileUpload控件，当用户点浏览的时候，下面只文件类型只显示一行（视频文件：flv）
主要做法：去掉原来的默认三种类型。要怎么做？[所有文件，图片，HTML]，添加自己想要的过滤条件。

Answer 1

Boolean fileOK = false;
        String path = Server.MapPath("~/admin/UploadImg/");
        String fileExtension = "";
        if (this.Ful_Img.HasFile)
        {
            fileExtension = System.IO.Path.GetExtension(this.Ful_Img.FileName).ToLower();
            String[] allowedExtensions = { ".bmp", ".gif", ".png", ".jpeg", ".jpg" };
            for (int i = 0; i < allowedExtensions.Length; i++)
            {
                if (fileExtension == allowedExtensions[i])
                {
                    fileOK = true;
                }
            }
        }
        if (fileOK)
        {
            try
            {
                String FileName = DateTime.Now.ToString("yyyyMMddhhmmss") + fileExtension;
                this.Ful_Img.PostedFile.SaveAs(path
                    + FileName);
                this.Txt_Imgname.Text = this.Txt_Imgname.Text+","+FileName;
                this.Lbl_Img.Text = this.Lbl_Img.Text+"第"+(this.Txt_Imgname.Text.Split(',').Length-1).ToString ()+"张图片成功 ";
                this.Ima_Pic.ImageUrl = "~/admin/UploadImg/" + FileName;
                this.Lbl_ImgOk.Visible = true;
            }
            catch
            {
                this.err_show.Visible = true;
            }

Answer 2

  <INPUT id="File1"  type="file"  name="File1" runat="server" Class="inputText" onfocus="javascript:ShowImage(this.value,document.getElementById('Image1'))">
 <asp:RegularExpressionValidator ID="FileValidator" runat="server" ControlToValidate="File1" Display="dynamic" ValidationExpression=".*([\.jpg]|[\.jpeg]|[\.jpe]|[\.gif]|[\.png]|[\.JPEG]|[\.JPG]|[\.GIF]|[\.bmp]|[\.BMP])$" ErrorMessage="jpg,jpeg,jpe,gif,png,JPEG,JPG,GIF,bmp,BMP"></asp:RegularExpressionValidator>  HttpPostedFile PostedFile = Files[i];
                if (PostedFile.ContentLength > 0)
                {
                    string FileName = PostedFile.FileName;
                    string AttachExt = FileName.Substring(FileName.LastIndexOf(".") + 1);                    string[] NoExPrentFile = new string[] { "exe", "asp", "aspx", "js", "php" };
                    bool IsUp = true;
                    for (int j = 0; j < NoExPrentFile.Length; j++)
                    {
                        if (AttachExt.Equals(NoExPrentFile[j]))
                        {
                            IsUp = false;
                        }
                    }
           }