每次点数据库还原都不可以。可不可以强制关闭数据库服务器的？请高手帮忙

if(!IsPostBack)
        {
            string cmdtxt1 = "Data Source=.;Initial Catalog=GCGL;Integrated Security=True";
            string cmdtxt2 = "Exec sp_helpdb";
            SqlConnection Con = new SqlConnection(cmdtxt1);
            Con.Open();
            SqlCommand mycommand = new SqlCommand(cmdtxt2, Con);
            SqlDataReader dr = mycommand.ExecuteReader();
            this.DropDownList1.DataSource = dr;
            this.DropDownList1.DataTextField = "name";
            this.DropDownList1.DataBind();
            dr.Close();
            Con.Close();

        }

 protected void btn_Restore_Click(object sender, EventArgs e)
    {
         string path = this.FileUpload1.PostedFile.FileName; //获得备份路径及数据库名称 
         string last = path.Substring(path.LastIndexOf(".") + 1);//获取文件的后缀名
         string dbname = this.DropDownList1.SelectedValue;
         if (last == "bak")    //判断是不是数据库备份文件
         {
             string cmdtxt1 = "Data Source=.;database='" + this.DropDownList1.SelectedValue + "';Integrated Security=True";
             string cmdtxt2 = "use master restore database " + dbname + " from disk='" + path + "'";
             SqlConnection Con = new SqlConnection(cmdtxt1);
             Con.Open();
             try
             {
                 SqlCommand Com = new SqlCommand(cmdtxt2, Con);
                 Com.ExecuteNonQuery();
                 Response.Write("<script language=javascript>alert('还原数据成功！'); location='Db_Restore.aspx'</script>");
             }
             catch (Exception ms)
             {
                 Response.Write(ms.Message);
                 Response.Write("<script language=javascript>alert('还原数据失败！') </script>");
             }
             finally
             {
                 Con.Close();
             }
         }
         else
         {
             Response.Write("<script language=javascript>alert('必须是数据库文件！'); </script>");
         }

    }