A class that provides system-level events and functions.

Properties

afterEvents: SystemAfterEvents

Returns a collection of after-events for system-level operations.

beforeEvents: SystemBeforeEvents

Returns a collection of before-events for system-level operations.

currentTick: number

Represents the current world tick of the server.

Methods

  • Beta

    Parameters

    Returns void

    Cancels the execution of a job queued via System.runJob.

  • Beta

    Parameters

    • runId: number

    Returns void

    Cancels the execution of a function run that was previously scheduled via System.run.

    import { system } from "@minecraft/server";

    const runId = system.run(() => {
    console.log("Running callback function...");
    });

    // Clear the run, so it will not run again.
    system.clearRun(runId);
  • Beta

    Parameters

    • callback: () => void

      Function callback to run at the next game tick.

    Returns number

    An opaque identifier that can be used with the clearRun function to cancel the execution of this run.

    Runs a specified function at the next available future time. This is frequently used to implement delayed behaviors and game loops. When run within the context of an event handler, this will generally run the code at the end of the same tick where the event occurred. When run in other code (a system.run callout), this will run the function in the next tick. Note, however, that depending on load on the system, running in the same or next tick is not guaranteed.

    import { system, world } from '@minecraft/server';

    function printEveryMinute() {
    try {
    // Minecraft runs at 20 ticks per second.
    if (system.currentTick % 1200 === 0) {
    world.sendMessage('Another minute passes...');
    }
    } catch (e) {
    console.warn('Error: ' + e);
    }

    system.run(printEveryMinute);
    }

    printEveryMinute();
    import { system } from "@minecraft/server";

    const runId = system.run(() => {
    console.log("Running callback function...");
    });
  • Beta

    Parameters

    • callback: () => void

      Functional code that will run when this interval occurs.

    • OptionaltickInterval: number

      An interval of every N ticks that the callback will be called upon.

    Returns number

    An opaque handle that can be used with the clearRun method to stop the run of this function on an interval.

    Runs a set of code on an interval.

    import { system, world } from '@minecraft/server';

    const intervalRunIdentifier = Math.floor(Math.random() * 10000);

    system.runInterval(() => {
    world.sendMessage('This is an interval run ' + intervalRunIdentifier + ' sending a message every 30 seconds.');
    }, 600);
  • Beta

    Parameters

    • generator: Generator<void, void, void>

      The instance of the generator to run.

    Returns number

    An opaque handle that can be used with System.clearJob to stop the run of this generator.

    Queues a generator to run until completion. The generator will be given a time slice each tick, and will be run until it yields or completes.

    import { BlockPermutation, DimensionLocation, world, ButtonPushAfterEvent, system } from '@minecraft/server';

    // A simple generator that places blocks in a cube at a specific location
    // with a specific size, yielding after every block place.
    function* blockPlacingGenerator(blockPerm: BlockPermutation, startingLocation: DimensionLocation, size: number) {
    for (let x = startingLocation.x; x < startingLocation.x + size; x++) {
    for (let y = startingLocation.y; y < startingLocation.y + size; y++) {
    for (let z = startingLocation.z; z < startingLocation.z + size; z++) {
    const block = startingLocation.dimension.getBlock({ x: x, y: y, z: z });
    if (block) {
    block.setPermutation(blockPerm);
    }
    yield;
    }
    }
    }
    }

    // When a button is pushed, we will place a 15x15x15 cube of cobblestone 10 blocks above it
    world.afterEvents.buttonPush.subscribe((buttonPushEvent: ButtonPushAfterEvent) => {
    const cubePos = buttonPushEvent.block.location;
    cubePos.y += 10;

    const blockPerm = BlockPermutation.resolve('minecraft:cobblestone');

    system.runJob(blockPlacingGenerator(blockPerm, { dimension: buttonPushEvent.dimension, ...cubePos }, 15));
    });
  • Beta

    Parameters

    • callback: () => void

      Functional code that will run when this timeout occurs.

    • OptionaltickDelay: number

      Amount of time, in ticks, before the interval will be called.

    Returns number

    An opaque handle that can be used with the clearRun method to stop the run of this function on an interval.

    Runs a set of code at a future time specified by tickDelay.

    import { TicksPerSecond, system } from "@minecraft/server";

    system.runTimeout(() => {
    console.log("Running callback function after delay...");
    }, TicksPerSecond * 5); // Tick delay of 5 seconds
  • Beta

    Parameters

    • ticks: number

    Returns Promise<void>

    This function can throw errors.

    minecraftcommon.EngineError