private void FormBriefcaseVLog_Load(object sender, EventArgs e)
        {
            vtbl = Portable.GetVersion(this.filepath, this.password);

            Binding bnd = new Binding("Text", vtbl, "VersionCode");

            this.tb_versioncode.DataBindings.Add(bnd);
            this.lb_filename.Text = this.filepath;
            DataTable tbl = Portable.GetVisitLog(this.filepath, this.password);

            this.dataGridView1.DataSource = tbl;
        }