/// <summary>
/// 异步查询，返回单一结果
/// </summary>
/// <param name="commandText">SQL语句</param>
/// <param name="commandParameters">参数集合</param>
/// <param name="transaction">使用指定的事务处理</param>
/// <param name="commandType">SQL语句 | 存储过程</param>
/// <returns>单一结果</returns>
#else
/// <summary>
/// async Query，Get result of One Object
/// </summary>
/// <param name="commandText">SQL statement</param>
/// <param name="commandParameters">SqlParameter Collection</param>
/// <param name="transaction">transaction</param>
/// <param name="commandType">Text | StoredProcedure</param>
/// <returns>Object</returns>
#endif
public static async Task <object> ExecuteScalarAsync(string commandText, SqlParameter[] commandParameters, MicroDBTransaction transaction, CommandType commandType = CommandType.Text)
{
if (transaction == null)
{
throw new InvalidOperationException(ERRMSG_TRANSACTION_IS_NULL, new ArgumentNullException("transaction"));
}
return(await AsyncSQLHelper.ExecuteScalarAsync(transaction.tran, commandType, commandText, commandParameters));
}
/// <summary>
/// 异步查询，返回单一结果
/// </summary>
/// <param name="commandText">SQL语句</param>
/// <param name="commandParameters">参数集合</param>
/// <param name="commandType">SQL语句 | 存储过程</param>
/// <param name="connectionAliasName">连接别名；如果没起别名，则使用默认的连接字符串</param>
/// <returns>单一结果</returns>
#else
/// <summary>
/// async Query，Get result of One Object
/// </summary>
/// <param name="commandText">SQL statement</param>
/// <param name="commandParameters">SqlParameter Collection</param>
/// <param name="commandType">Text | StoredProcedure</param>
/// <param name="connectionAliasName">the Alias Name of Connection (if not pass name,it will use the DEFAULT name instead.)</param>
/// <returns>Object</returns>
#endif
public static async Task <object> ExecuteScalarAsync(string commandText, SqlParameter[] commandParameters, string connectionAliasName = ALIAS_NAME_DEFAULT, CommandType commandType = CommandType.Text)
{
return(await AsyncSQLHelper.ExecuteScalarAsync(GetConnection(connectionAliasName), commandType, commandText, commandParameters));
}