convert code vb.net to c#

DateTime datefrom = DateTime.Now.Subtract(new TimeSpan(1, 0, 0, 0, 0)); // move back time
DateTime dateto = DateTime.Now;

TimeSpan tmp = dateto - datefrom;
long diff = (long)tmp.TotalMinutes;

// or the one liner
long diff = (long)(dateto - datefrom).TotalMinutes;