/// <summary>
/// Adds a value to the specified date.
/// </summary>
/// <param name="type">
/// The type of date difference that will be added.
/// </param>
/// <param name="datetime">
/// The date/time.
/// </param>
/// <param name="value">
/// The value to add.
/// </param>
/// <returns>
/// The <see cref="DateTime"/>.
/// </returns>
/// <exception cref="Exception">
/// Thrown when an invalid date difference type is provided.
/// </exception>
private static DateTime DateAdd(DateDiffType type, DateTime datetime, double value)
{
switch (type)
{
case DateDiffType.Millisecond:
return(datetime.AddMilliseconds(value));
case DateDiffType.Second:
return(datetime.AddSeconds(value));
case DateDiffType.Minute:
return(datetime.AddMinutes(value));
case DateDiffType.Hour:
return(datetime.AddHours(value));
case DateDiffType.Day:
return(datetime.AddDays(value));
case DateDiffType.Week:
return(datetime.AddDays(value * 7));
case DateDiffType.Month:
return(datetime.AddMonths((int)value));
case DateDiffType.Year:
return(datetime.AddYears((int)value));
default:
throw new Exception("Invalid date diff type.");
}
}
public string DateDiff(DateDiffType type)
{
switch (type)
{
case DateDiffType.Day:
return(" DATEDIFF({1},{0}) ");
case DateDiffType.Hour:
case DateDiffType.Minute:
default:
throw new NotImplementedException("SQLite DateDiff函数不支持Hour Minute此格式");
}
}
/// <summary>
/// 时间差
/// </summary>
/// <param name="dateStart"></param>
/// <param name="dateEnd"></param>
/// <param name="type">0：天数，1：月数，2：年数，</param>
/// <returns></returns>
private static int DateDiff(this DateTime dateStart, DateTime dateEnd, DateDiffType dateDiffType = DateDiffType.Day)
{
TimeSpan sp = dateEnd.Subtract(dateStart);
return(dateDiffType switch
{
//DateDiffType.Year => sp.Minutes,
//DateDiffType.Month => sp.Minutes,
DateDiffType.Day => sp.Days,
DateDiffType.Hour => sp.Hours,
DateDiffType.Minute => sp.Minutes,
DateDiffType.Second => sp.Seconds,
_ => sp.Days,
});
public string DateDiff(DateDiffType type)
{
switch (type)
{
case DateDiffType.Day:
return(" DATEDIFF(DAY,{0},{1}) ");
case DateDiffType.Hour:
return(" DATEDIFF(HOUR,{0},{1}) ");
case DateDiffType.Minute:
return(" DATEDIFF(MINUTE,{0},{1}) ");
default:
throw new NotImplementedException("DateDiff函数不支持此格式");
}
}
/// <summary>
/// Calculates the difference between two dates.
/// </summary>
/// <param name="type">
/// The type of the difference to calculate.
/// </param>
/// <param name="first">
/// The first date.
/// </param>
/// <param name="second">
/// The second date.
/// </param>
/// <returns>
/// The difference.
/// </returns>
/// <exception cref="Exception">
/// Thrown when an invalid date difference type is provided.
/// </exception>
private static int DateDiff(DateDiffType type, DateTime first, DateTime second)
{
if (second > first)
{
var tmp = second;
second = first;
first = tmp;
}
switch (type)
{
case DateDiffType.Millisecond:
return((int)(second - first).TotalMilliseconds);
case DateDiffType.Second:
return((int)(second - first).TotalSeconds);
case DateDiffType.Minute:
return((int)(second - first).TotalMinutes);
case DateDiffType.Hour:
return((int)(second - first).TotalHours);
case DateDiffType.Day:
return((int)(second - first).TotalDays);
case DateDiffType.Week:
return((int)(second - first).TotalDays / 7);
case DateDiffType.Month:
return((second.Year - first.Year) * 12 + second.Month - first.Month + (second.Day >= first.Day ? 0 : -1));
case DateDiffType.Year:
var years = second.Year - first.Year;
return(years - (first > second.AddYears(-years) ? 1 : 0));
default:
throw new Exception("Invalid date diff type.");
}
}
public static int DateDiff(this DateTime left, DateTime right, DateDiffType type = DateDiffType.Day)
{
if (type == DateDiffType.Year)
{
return(left.Year - right.Year);
}
if (type == DateDiffType.Month)
{
return(((left.Year - right.Year) * 12) + (left.Month - right.Month));
}
if (left.Year == right.Year && type == DateDiffType.Week)
{
return(left.GetWeekOfYear() - right.GetWeekOfYear());
}
int days = (int)Math.Floor((left - right).TotalDays);
if (type == DateDiffType.Week)
{
return((int)Math.Floor(days / 7.0));
}
return(days);
}
public static int DateDiff(DateDiffType type, dynamic startTime, dynamic endTime)
{
throw new NotImplementedException("SQL解析函数无需实现");
}
public string DateDiff(DateDiffType type)
{
throw new NotImplementedException("Oracle DateDiff函数不支持此格式");
}
public static int DateDiff(DateDiffType type, DateTime StartTime, DateTime EndTime)
{
if (StartTime.CompareTo(EndTime) > 0)
{
return 0;
}
switch (type)
{
case DateDiffType.Year:
return EndTime.Year - StartTime.Year;
case DateDiffType.Month:
return Convert.ToInt32((EndTime - StartTime).TotalDays) / 30;
case DateDiffType.Day:
return Convert.ToInt32((EndTime - StartTime).TotalDays);
case DateDiffType.Min:
return Convert.ToInt32((EndTime - StartTime).TotalMinutes);
case DateDiffType.Second:
return Convert.ToInt32((EndTime - StartTime).TotalSeconds);
default:
return 0;
}
}
public DateDiff2(DateDiffType type)
{
this.type = type;
}
public DateDiff(DateDiffType type, string compareTo)
{
this.type = type;
this.compareTo = compareTo;
}
