/// <summary>
/// 根据统计类型返回统计值
/// </summary>
/// <param name="statisticsResults"></param>
/// <param name="eType">统计值类型</param>
/// <returns></returns>
private static double StatisticsByType(IStatisticsResults statisticsResults, EStatisticsType eType)
{
switch (eType)
{
case EStatisticsType.Count: return(statisticsResults.Count);
case EStatisticsType.Maximum: return(statisticsResults.Maximum);
case EStatisticsType.Mean: return(statisticsResults.Mean);
case EStatisticsType.Minimum: return(statisticsResults.Minimum);
case EStatisticsType.Sum: return(statisticsResults.Sum);
case EStatisticsType.StandardDeviation: return(statisticsResults.StandardDeviation);
default: throw new NotImplementedException();
}
}
/// <summary>
/// 获得字段统计值
/// </summary>
/// <param name="table">统计的表格</param>
/// <param name="fieldName">统计的字段</param>
/// <param name="whereClause">统计条件</param>
/// <param name="eType">统计值类型</param>
/// <returns></returns>
public static double Statistics(this ITable table, string fieldName, string whereClause, EStatisticsType eType)
{
IStatisticsResults statisticsResults = Statistics(table, fieldName, whereClause);
return(StatisticsByType(statisticsResults, eType));
}