ISharedCounter Interface

A shared object that holds a number that can be incremented or decremented.

This API is provided for existing users, but is not recommended for new users.

To use, import via @fluidframework/counter/legacy.

For more information about our API support guarantees, see here.

Signature

export interface ISharedCounter extends ISharedObject<ISharedCounterEvents>

Extends: ISharedObject<ISharedCounterEvents>

Remarks

Note that SharedCounter only operates on integer values. This is validated at runtime.

Usage

Example 1

Creating a SharedCounter

First, get the factory and call create(runtime, id) with a runtime and string ID:

const factory = SharedCounter.getFactory();
const counter = factory.create(this.runtime, id);

The initial value of a new SharedCounter is 0. If you wish to initialize the counter to a different value, you may call increment(incrementAmount) before attaching the Container, or before inserting it into an existing shared object.

Example 2

Using the SharedCounter

Once created, you can call increment(incrementAmount) to modify the value with either a positive or negative number:

counter.increment(10); // add 10 to the counter value
counter.increment(-5); // subtract 5 from the counter value

To observe changes to the value (including those from remote clients), register for the incremented event:

counter.on("incremented", (incrementAmount, newValue) => {
    console.log(`The counter incremented by ${incrementAmount} and now has a value of ${newValue}`);
});

Properties

Property	Alerts	Type	Description
value	Beta	number	The counter value.

Methods

Method	Alerts	Return Type	Description
increment(incrementAmount)	Beta	void	Increments or decrements the value. Must only increment or decrement by a whole number value.

Property Details

value

The counter value.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

value: number;

Type: number

Remarks

Must be a whole number.

Method Details

increment

Increments or decrements the value. Must only increment or decrement by a whole number value.

This API is provided for existing users, but is not recommended for new users.

For more information about our API support guarantees, see here.

Signature

increment(incrementAmount: number): void;

Parameters

Parameter	Type	Description
incrementAmount	number	A whole number to increment or decrement by.