MultiColumn ComboBox Bind Datasource

            m_oBankAccountCollection.Clear();

            m_oBankAccountCollection.List();
            m_oBankAccountCollection.Sort(BankAccountCollection.BankAccountFields.AccountNo, true);

            ddlmcBankAccountInput.DataSource = m_oBankAccountCollection;
            ddlmcBankAccountInput.DisplayMember = "BankName";
            ddlmcBankAccountInput.ValueMember = "BankAccountId";

            RadGridView oRadGridView = this.ddlmcBankAccountInput.EditorControl;
            oRadGridView.MasterTemplate.AutoGenerateColumns = false;
            oRadGridView.Columns.Add(new GridViewTextBoxColumn("AccountNo"));
            oRadGridView.Columns.Add(new GridViewTextBoxColumn("BankName"));
            oRadGridView.Columns.Add(new GridViewTextBoxColumn("AccountName"));
            GridViewTextBoxColumn oGridViewTextBoxColumn = new GridViewTextBoxColumn("BankAccountId");
            oGridViewTextBoxColumn.VisibleInColumnChooser = false;
            oRadGridView.Columns.Add(oGridViewTextBoxColumn);