Task Constraints

Source code

TypeScript ts

import { GANTT_CONSTRAINTS_DEADLINES_DEMO } from './gantt-advanced-data';
import { loadAdvancedGanttDemo } from './GanttAdvancedVanillaDemo';

export function load(parentSelector: string) {
  return loadAdvancedGanttDemo(parentSelector, GANTT_CONSTRAINTS_DEADLINES_DEMO);
}

Vue vue

<template>
  <GanttAdvancedDemo :demo="GANTT_CONSTRAINTS_DEADLINES_DEMO" />
</template>

<script setup lang="ts">
import GanttAdvancedDemo from './GanttAdvancedDemo.vue';
import { GANTT_CONSTRAINTS_DEADLINES_DEMO } from './gantt-advanced-data';
</script>

React tsx

import React from 'react';
import GanttAdvancedDemo from './GanttAdvancedReactDemo';
import { GANTT_CONSTRAINTS_DEADLINES_DEMO } from './gantt-advanced-data';

export default function GanttConstraintsDeadlines() {
  return <GanttAdvancedDemo demo={GANTT_CONSTRAINTS_DEADLINES_DEMO} />;
}

Angular ts

import { Component, NO_ERRORS_SCHEMA, ViewEncapsulation } from '@angular/core';
import { RevoGrid } from '@revolist/angular-datagrid';
import { GanttAdvancedAngularBase } from './GanttAdvancedAngularBase';
import { GANTT_CONSTRAINTS_DEADLINES_DEMO } from './gantt-advanced-data';

@Component({
  selector: 'gantt-constraints-deadlines-grid',
  standalone: true,
  // Allows Angular demos to bind RevoGrid plugin props that are not wrapper inputs.
  schemas: [NO_ERRORS_SCHEMA],
  imports: [RevoGrid],
  template: `<revo-grid style="min-height: 560px" [theme]="theme" [hideAttribution]="true" [plugins]="plugins" [source]="tasks" [columns]="columns" [gantt]="ganttConfig" [ganttDependencies]="dependencies" [ganttCalendars]="calendars" [ganttResources]="resources" [ganttAssignments]="assignments"></revo-grid>`,
  encapsulation: ViewEncapsulation.None,
})
export class GanttConstraintsDeadlinesGridComponent extends GanttAdvancedAngularBase {
  protected readonly demo = GANTT_CONSTRAINTS_DEADLINES_DEMO;
}

Constraints are explicit fields on a task that override or refine the automatic forward-pass scheduling:

{
  id: 'integration',
  name: 'External Integration',
  constraintType: 'start-no-earlier-than',
  constraintDate: '2026-05-04',
  // other task fields
}

Supported Constraint Types

Constraint	MSP equivalent	Behavior
start-no-earlier-than	SNET	Start on or after the constraint date.
start-no-later-than	SNLT	Start on or before the constraint date.
finish-no-earlier-than	FNET	Finish on or after the constraint date.
finish-no-later-than	FNLT	Finish on or before the constraint date.
must-start-on	MSO	Start exactly on the constraint date.
must-finish-on	MFO	Finish exactly on the constraint date.

Soft vs. Hard Constraints

Soft Constraints (SNET, SNLT, FNET, FNLT)

These constraints define a legal window for the task. If the dependency propagation moves the task outside this window, the scheduler will:

• Adjust the date to the nearest legal bound (if possible).
• Report a constraint-window-conflict if the dependency and constraint windows do not overlap.

Hard Constraints (MSO, MFO)

Hard constraints are authoritative. They pin the task to an exact date, even if it violates dependencies.

• If a dependency requires a different date, the scheduler reports a hard-constraint-conflict or dependency-constraint-conflict.
• The task date is NOT moved to satisfy the dependency; the constraint wins.

Note

Microsoft Project also exposes flexible ASAP and ALAP as constraint types. RevoGrid models those at project level with scheduleFrom, not as per-task constraintType values.