public static object DateDiff(string datepart, object o1, object o2)
{
if (string.IsNullOrEmpty(datepart))
{
throw new InvalidOperationException("Datepart can not be empty.");
}
var dp = DateParts.GetDatePart(datepart);
if (EDatePart.Unknown == dp)
{
throw new InvalidOperationException($"'{datepart}' is not a recognized datediff option.");
}
if (IsNull(o1) || IsNull(o2))
{
return(DBNull.Value);
}
DateTime dt1;
try
{
dt1 = Convert.ToDateTime(o1);
}
catch
{
throw new InvalidOperationException($"Conversion failed when converting date and/or time from '{o1.ToString()}'.");
}
DateTime dt2;
try
{
dt2 = Convert.ToDateTime(o2);
}
catch
{
throw new InvalidOperationException($"Conversion failed when converting date and/or time from '{o2.ToString()}'.");
}
switch (dp)
{
case EDatePart.Year:
return(dt2.Year - dt1.Year);
case EDatePart.Quarter:
return((dt2.Year - dt1.Year) * 4 + (dt2.Month - dt1.Month) / 3);
case EDatePart.Month:
return((dt2.Year - dt1.Year) * 12 + (dt2.Month - dt1.Month));
case EDatePart.DayOfYear:
case EDatePart.Day:
case EDatePart.WeekDay:
var days = (dt2.Date - dt1.Date).TotalDays;
return(Math.Round(days));
case EDatePart.Week:
var weeks = (dt2.Date - dt1.Date).TotalDays / 7;
return(Math.Round(weeks));
case EDatePart.Hour:
var hours = (dt2 - dt1).TotalHours;
return(Math.Round(hours));
case EDatePart.Minute:
var minutes = (dt2 - dt1).TotalMinutes;
return(Math.Round(minutes));
case EDatePart.Second:
var seconds = (dt2 - dt1).TotalSeconds;
return(Math.Round(seconds));
case EDatePart.MilliSecond:
return((dt2 - dt1).TotalMilliseconds);
default:
throw new InvalidOperationException($"'{datepart}' is not a recognized datediff option.");
}
}
public static object DatePart(string datepart, object o)
{
if (string.IsNullOrEmpty(datepart))
{
throw new InvalidOperationException("Datepart can not be empty.");
}
var dp = DateParts.GetDatePart(datepart);
if (EDatePart.Unknown == dp)
{
throw new InvalidOperationException($"'{datepart}' is not a recognized datepart option.");
}
if (IsNull(o))
{
return(DBNull.Value);
}
DateTime dt;
try
{
dt = Convert.ToDateTime(o);
}
catch
{
throw new InvalidOperationException($"Conversion failed when converting date and/or time from '{o.ToString()}'.");
}
switch (dp)
{
case EDatePart.Year:
return(dt.Year);
case EDatePart.Quarter:
return((dt.Month / 3) + 1);
case EDatePart.Month:
return(dt.Month);
case EDatePart.DayOfYear:
return(dt.DayOfYear);
case EDatePart.Day:
return(dt.Day);
case EDatePart.WeekDay:
return((int)dt.DayOfWeek + 1);
case EDatePart.Week:
return(CultureInfo.CurrentCulture.Calendar.GetWeekOfYear(dt, CalendarWeekRule.FirstDay, DayOfWeek.Sunday));
case EDatePart.Hour:
return(dt.Hour);
case EDatePart.Minute:
return(dt.Minute);
case EDatePart.Second:
return(dt.Second);
case EDatePart.MilliSecond:
return(dt.Millisecond);
default:
throw new InvalidOperationException($"'{datepart}' is not a recognized datepart option.");
}
}
public static object DateAdd(string datepart, int num, object o)
{
if (string.IsNullOrEmpty(datepart))
{
throw new InvalidOperationException("Datepart can not be empty.");
}
var dp = DateParts.GetDatePart(datepart);
if (EDatePart.Unknown == dp)
{
throw new InvalidOperationException($"'{datepart}' is not a recognized dateadd option.");
}
if (IsNull(o))
{
return(DBNull.Value);
}
DateTime dt;
try
{
dt = Convert.ToDateTime(o);
}
catch
{
throw new InvalidOperationException($"Conversion failed when converting date and/or time from '{o.ToString()}'.");
}
switch (dp)
{
case EDatePart.Year:
return(dt.AddYears(num));
case EDatePart.Quarter:
return(dt.AddMonths(num * 3));
case EDatePart.Month:
return(dt.AddMonths(num));
case EDatePart.DayOfYear:
case EDatePart.Day:
case EDatePart.WeekDay:
return(dt.AddDays(num));
case EDatePart.Week:
return(dt.AddDays(num * 7));
case EDatePart.Hour:
return(dt.AddHours(num));
case EDatePart.Minute:
return(dt.AddMinutes(num));
case EDatePart.Second:
return(dt.AddSeconds(num));
case EDatePart.MilliSecond:
return(dt.AddMilliseconds(num));
default:
throw new InvalidOperationException($"'{datepart}' is not a recognized dateadd option.");
}
}
