求用C#编程，实现如图rn 相同值时的时间间隔

[xiaohua7988]

求用C#编程，实现如图rn 相同值时的时间间隔



我自己试着编了一下没有实现，求大神指导下逻辑

 static void Main(string[] args)
        {

            foopdata foop = new foopdata();
            DataTable da = foop.GetTable();
            for (int i = 0; i < da.Rows.Count; i++)
            {

                int flag = i;
                DateTime dt1 = Convert.ToDateTime(da.Rows[flag]["TIME"]);
                 for (int k = flag + 1; k < da.Rows.Count; k++) {
                        if (da.Rows[flag]["rn"] == da.Rows[flag + 1]["rn"]) {

                        k++;

                        }
                        
                    DateTime dt2 = Convert.ToDateTime(da.Rows[k]["TIME"]);
                     TimeSpan ts = dt2.Subtract(dt1);
                       double jiange = ts.TotalSeconds;
                       Console.WriteLine(jiange);
                    i = k + 1;
                }  

}
            Console.Read();
}
}
}

[xuzuning]

记下行号，当 rn 变化时，计算并记下当前的行号

[吉普赛的歌]

select 
    rn,
    datediff(second, min([Time]),  max([Time]) ) as diffSeconds
from t 
group by rn
order by rn