Get DB Key Columns For Selected Table.cs

/// <summary>
        /// Get primary key columns for selected table
        /// </summary>
        private void GetKeyColumns()
        {
            // New key column class
            _tableKeyColumnsArrayList = new List<TableKeyColumns>();

            // Get db name from settings file
            var database = Properties.Settings.Default.Database;

            // Select primary ket columns from sql for selected table
            var sql = "USE [" + database + "] SELECT COLUMN_NAME As KeyColumns FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE with (nolock) WHERE OBJECTPROPERTY(OBJECT_ID(CONSTRAINT_SCHEMA + '.' + QUOTENAME(CONSTRAINT_NAME)), 'IsPrimaryKey') = 1 AND TABLE_NAME = '" + TableName + "' AND TABLE_SCHEMA = 'dbo'";

            using (var connection = new SqlConnection(ConnectionString))
            {
                var command = new SqlCommand(sql, connection);
                connection.Open();
                var reader = command.ExecuteReader();
                try
                {
                    while (reader.Read())
                    {
                        // Add primary key columns to class list for later usage
                        _tableKeyColumnsArray = new TableKeyColumns
                        {
                            ColumnName = reader["KeyColumns"].ToString(),
                        };
                        _tableKeyColumnsArrayList.Add(_tableKeyColumnsArray);
                    }
                }
                catch (Exception ex)
                {
                    reader.Close();
                    // Show alert on error - no message boxes, using popups
                    var alertInfo = new AlertInfo("Error", ex.Message);
                    var control = new AlertControl { FormLocation = AlertFormLocation.BottomRight };
                    control.Show(ParentForm, alertInfo);
                }
                reader.Close();
            }

        }