DHTMLX Planning Engine Documentation

TimeUnit#

The unit that a task's duration and a link's lag are counted in. The project default is SchedulingConfig.DurationUnit. A task overrides it with TaskData.DurationUnit, and a link with LinkData.LagUnit.

Declaration#

namespace Plen;

public enum TimeUnit { Minute, Hour, Day }

default(TimeUnit) is Minute. The default of SchedulingConfig.DurationUnit is Day.

Values#

Value Description
Minute Working minutes. Amounts are rounded to whole minutes when a date is placed.
Hour Working hours of 60 minutes. Amounts are rounded to whole minutes when a date is placed.
Day Working days. A working date of any length counts as one day, and a placed date keeps its time of day. Amounts are rounded to whole days when a date is placed.

Weeks, months and years have no value.

A duration or lag in these units is working time: non-working time on the task's calendar doesn't count. TaskData.LevelingDelay and Pause lengths use the same unit as elapsed time, where Day means 24 hours.

Where it's used#

Member Type Meaning
SchedulingConfig.DurationUnit TimeUnit Project default, Day unless set.
TaskData.DurationUnit TimeUnit? Unit of the task's Duration, LevelingDelay and Pauses. null uses the project default.
LinkData.LagUnit TimeUnit? Unit of the link's Lag. null uses the project default.
LinkAdd.LagUnit TimeUnit? Same as LinkData.LagUnit, for a link added after the first solve.
LinkUpdate.LagUnit Patch<TimeUnit> Changes the unit of an existing link's lag.

TimeUnit has no parse or spelling helpers. In JSON the values are spelled "minute", "hour" and "day"; the Plen.Wire package reads and writes them. See Exchange JSON with a client.

Example#

The project counts in days, one task counts in hours, and one link's lag is in minutes:

using Plen;

var start = Moment.FromYmdHm(2026, 4, 6, 8, 0)
    ?? throw new InvalidOperationException("invalid date");

var data = new ProjectData
{
    Config = new SchedulingConfig { DurationUnit = TimeUnit.Day },
    Tasks =
    [
        new TaskData(1) { StartDate = start, Duration = 2.0 },
        new TaskData(2) { StartDate = start, Duration = 6.0, DurationUnit = TimeUnit.Hour },
    ],
    Links =
    [
        new LinkData { Id = "a", Source = 1, Target = 2, Lag = 30.0, LagUnit = TimeUnit.Minute },
    ],
};

var result = Engine.Schedule(data, new SolveOptions());
foreach (var update in result.Updates)
{
    Console.WriteLine(update);
}