private void btn_SelectColumns_Click(object sender, EventArgs e) { FrmColumnSelection frm = new FrmColumnSelection(); frm.Selectee = this.GridView; frm.SelectedColumns = GetAllVisiableColumns(); if (frm.ShowDialog() == DialogResult.OK) { string[] cols = frm.SelectedColumns; if (cols != null && cols.Length > 0) { string temp = string.Join(",", cols); AppSettings.CurrentSetting.SaveConfig(string.Format("{0}_Columns", this.GetType().Name), temp); ShowVisableColumns(); } } }