asp.net c# 数据库备份

protected void btnsearch_ServerClick(object sender, EventArgs e)
    {
        string lujing=this.Text2.Value.ToString().Trim();
        string shujuku = this.jine.Value;
        string wenjianming = this.Text1.Value.ToString().Trim();
        if (wenjianming.IndexOf(".bak") == -1)
        {
            Page.ClientScript.RegisterStartupScript(Page.GetType(), "", "<script>alert('备份文件名格式错误！');</script>");
            return;
        }
        if (System.IO.File.Exists(lujing))
        {
            //则表示存在
        }
        else
        {
            //创建该文件夹 
            System.IO.Directory.CreateDirectory(lujing);
        }
        string wenjj = lujing + @"\" + wenjianming;
        if (System.IO.File.Exists(wenjj))
        {
            Page.ClientScript.RegisterStartupScript(Page.GetType(), "", "<script>alert('备份文件名已存在，请重新命名！');</script>");
            return;
        }
        string cmd1 = "backu