using System.IO;protected void Page_Load(object sender, EventArgs e){if (!IsPostBack)        {            BindFileName();        }}    public void BindFileName()    {        DropDownList1.Items.Clear();        string path = Server.MapPath("你的文件夹的路径");        DirectoryInfo di = new DirectoryInfo(path);        foreach (FileInfo fi in di.GetFiles())        {            ListItem li = new ListItem();            li.Value = fi.FullName;            li.Text = fi.Name;            DropDownList1.Items.Add(li);        }    }//把文件夹里的文件名绑定到DropDownList1protected void Button3_Click(object sender, EventArgs e)    {//这里是删除按钮        File.Delete(DropDownList1.SelectedValue);        BindFileName();        Response.Write("");    }