Class Promise<T>

A Promise is used for operations that retrieve data asynchronously. Use this object to determine the status of the operation (that is, whether it has completed), and the resulting data.

Inheritance

object

CustomYieldInstruction

Promise<T>

Implements

IEnumerator

Inherited Members

CustomYieldInstruction.MoveNext()

CustomYieldInstruction.Reset()

CustomYieldInstruction.Current

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

Namespace: UnityEngine.XR.ARSubsystems

Assembly: solution.dll

Syntax

public abstract class Promise<T> : CustomYieldInstruction, IEnumerator

Type Parameters

Name	Description
T	The type of information the asynchronous operation retrieves.

Remarks

Since Promise<T> derives from CustomYieldInstruction, you can yield return on a Promise in a coroutine. If you prefer not to use the Promise as a coroutine, you can manually check keepWaiting to determine if the operation has completed. Once the operation is complete, you can get the resulting value from result.

Examples

Example usage in a coroutine:

IEnumerator MyCoroutine()
{
    var promise = GetDataAsync();
    yield return promise;
    Debug.LogFormat("Operation complete. Result = {0}", promise.result);
}

Properties

Name	Description
keepWaiting	Will return true as long as the operation has not yet completed.
result	The result of the asynchronous operation. Not valid until keepWaiting returns false.

Methods

Name	Description
CreateResolvedPromise(T)	Creates a resolved promise (that is, a promise that is already complete).
OnKeepWaiting()	Invoked whenever keepWaiting is queried. Implement this to perform per-frame updates.
Resolve(T)	The creator of the Promise<T> should call this when the asynchronous operation completes.