IPrjTask.ConstraintDate

Syntax

ConstraintDate: DateTime;

Description

The ConstraintDate property determines a date constraint for task execution.

Comments

The property is relevant on using a specific type of task constraint by time.

Example

To execute the example, add a link to the ProjectPlanning system assembly.

Sub UserProc;
Var
    Project: IPrjProject;
    Tasks: IPrjTaskCollection;
    Task: IPrjTask;
    Depend: IPrjTaskDependency;
    FPeriod: IPrjTaskPeriod;
    i: Integer;
Begin
    Project := New PrjProject.Create;
    // Set project start date
    Project.StartDate := DateTime.Parse("20.02.2020");
    Project.UseStartDate := True;
    // Get collection of project tasks
    Tasks := Project.Tasks;
    // Add the first task
    Task := Tasks.Add;
    Task.Key := 1;
    Task.Name := "№1";
    Task.PlanPeriod.Duration := 7;
    Task.ConstraintType := PrjTaskConstraintType.StartNoEarlierThan;
    Task.ConstraintDate := DateTime.Parse("25.02.2020");
    // Add the second task
    Task := Tasks.Add;
    Task.Key := 2;
    Task.Name := "№2";
    Task.PlanPeriod.Duration := 10;
    Depend := Task.Dependencies.Add;
    Depend.PredecessorTaskKey := 1;
    Depend.Type := PrjTaskDependencyType.FinishToFinish;
    // Run calculation
    Project.Plan;
    For i := 0 To Tasks.Count - 1 Do
        Task := Tasks.Item(i);
        FPeriod := Task.ForecastPeriod;
        Debug.WriteLine("Task execution " + Task.Name + " from " +
        FPeriod.StartDate.ToString + " to " + FPeriod.FinishDate.ToString +
        " (duration: " + FPeriod.Duration.ToString + " days)");
    End For;
End Sub UserProc;

After executing the example, the project will be calculated considering the specified conditions:

The first task execution starts no earlier than the specified date.
The second task end date matches the first task end date.

The console displays the calculation result:

The first task execution from 25.02.2020 00:00:00 to 02.03.2020 00:00:00 (duration: 7 days)

The second task execution from 22.02.2020 00:00:00 to 02.03.2020 00:00:00 (duration: 10 days)