IPrjProject.Contradictions

Syntax

Contradictions: IPrjContradictionsCollection;

Description

The Contradictions property returns the collection of task completion time contradictions.

Example

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

Sub UserProc;
Var
    Project: IPrjProject;
    Tasks: IPrjTaskCollection;
    Task: IPrjTask;
    Depend: IPrjTaskDependency;
    Plan, FPeriod: IPrjTaskPeriod;
    i: Integer;
    Contradiction: IPrjContradiction;
    Collection: IPrjContradictionsCollection;
    Dependency: String;
Begin
    Project := New PrjProject.Create;
    // Get collection of project tasks
    Tasks := Project.Tasks;
    // Add the first task
    Task := Project.Tasks.Add;
    Task.Key := 1;
    Task.Name := "Task №1";
    // Set the scheduled task execution period
    Plan := Task.PlanPeriod;
    Plan.Duration := 3;
    Plan.StartDate := DateTime.Parse("08.02.2020");
    Plan.FinishDate := DateTime.Parse("10.02.2020");
    // Set a time constraint for task execution
    Task.ConstraintType := PrjTaskConstraintType.MustFinishOn;
    Task.ConstraintDate := DateTime.Parse("10.02.2020");
    // Add the second task
    Task := Project.Tasks.Add;
    Task.Key := 2;
    Task.Name := "Task №2";
    // Set the scheduled task execution period
    Plan := Task.PlanPeriod;
    Plan.Duration := 3;
    Plan.StartDate := DateTime.Parse("11.02.2020");
    Plan.FinishDate := DateTime.Parse("13.02.2020");
    // Set a time constraint for task execution
    Task.ConstraintType := PrjTaskConstraintType.MustStartOn;
    Task.ConstraintDate := DateTime.Parse("17.02.2020");
    // Set link between tasks
    Depend := Task.Dependencies.Add;
    Depend.PredecessorTaskKey := 1;
    Depend.Type := PrjTaskDependencyType.FinishToStart;
    // Run calculation
    Project.Plan;
    // Display planned and forecasted periods of tasks execution to the console
    For i := 0 To Tasks.Count - 1 Do
        Task := Tasks.Item(i);
        FPeriod := Task.ForecastPeriod;
        Plan := Task.PlanPeriod;
        Debug.WriteLine(Task.Name + ":");
        Debug.WriteLine("  Plan: " + Plan.StartDate.ToString + " - " + Plan.FinishDate.ToString);
        Debug.WriteLine("  Forecast: " + FPeriod.StartDate.ToString + " - " + FPeriod.FinishDate.ToString);
    End For;
    Debug.WriteLine("=========");
    // Determine contradiction in task execution period
    Collection := Project.Contradictions;
    If Collection.Count <> 0 Then
        For i := 0 To Project.Contradictions.Count - 1 Do
            Contradiction := Collection.Item(i);
            Select Case  Contradiction.Dependency.Type As Integer
                Case 0: Dependency := "end-start";
                Case 1: Dependency := "start-start";
                Case 2:  Dependency := "end-end";
                Case 3: Dependency := "start-end";
            End Select;
            Debug.WriteLine("Predecessor task: " + Contradiction.Predecessor.Name);
            Debug.WriteLine("Link between tasks: " + Dependency);
            Debug.WriteLine("Linked task: " + Contradiction.Follower.Name);
            Debug.WriteLine("Period contradiction: " + Contradiction.Difference.ToString + " days");
        End For;
    End If;
End Sub UserProc;

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

The first task must be completed on 10.02.2020.
The second task must start on 17.02.2020.
The second task execution start date depends on the first task en date.

The console displays scheduled and forecasted task execution periods and parameters for period contradiction:

Task 1:

Plan: 08.02.2020 00:00:00 - 10.02.2020 00:00:00

Forecast: 08.02.2020 00:00:00 - 10.02.2020 00:00:00

Task 2:

Plan: 11.02.2020 00:00:00 - 13.02.2020 00:00:00

Forecast: 17.02.2020 00:00:00 - 19.02.2020 00:00:00

=========

Predecessor task: Task 1

Link between tasks: start-end

Linked task: Task 2

Period contradiction: 6 days