API Reference

Complete reference for FoxCoreClass, the Task object and the task procedure signature.

FoxCoreClass

Main FoxCore class. COM ProgId: FoxCore.FoxCoreClass. Entry point for creating and managing async tasks.

Methods

Signature	Description
`Run(lcProc AS STRING, loParams AS OBJECT) AS Task`	Executes lcProc asynchronously. Returns a Task object immediately. loParams can be any VFP object.
`RunAll(@laProcs AS ARRAY) AS OBJECT`	Executes an array of procedure names in parallel. Returns an array of Task objects, one per entry.
`Cancel(loTask AS Task) AS VOID`	Requests cancellation of loTask. The Task moves to Status="Cancelled". The task must check status to respond to cancellation.
`WaitFor(loTask AS Task [, lnTimeoutMs AS NUMBER]) AS BOOLEAN`	Blocks until loTask finishes or lnTimeoutMs elapses. Returns .T. if the task completed, .F. on timeout. lnTimeoutMs is optional (0 = no limit).
`GetActiveTasks() AS ARRAY`	Returns an array with all Tasks in Pending or Running state.
`SetLicensePath(lcPath AS STRING) AS VOID`	Specifies the path where FoxCore will look for FoxCore.lic. Call before Run() if the file is not in the application folder.

Properties

Property	Type	Description
`Version`	STRING	Installed FoxCore version string. Read-only.
`MaxWorkers`	NUMBER	Maximum number of concurrent tasks. Default: 8. Maximum: 32.

Note on MaxWorkers: The default value of MaxWorkers is 8. The absolute maximum is 32. Each worker is an independent VFP instance; setting this too high can saturate system memory.

Task

Object returned by Run() and RunAll(). Represents an individual task and exposes its status, progress and result.

Task properties

Property	Type	Description
`Id`	STRING	Unique task identifier (GUID).
`Status`	STRING	Current state: Pending, Running, Done, Failed, Cancelled.
`Progress`	NUMBER	Progress 0-100. Set by the task procedure.
`Result`	ANY	Result value on completion. Set by the task procedure.
`Error`	STRING	Error message when Status="Failed".
`StartedAt`	DATETIME	Date/time when the task started executing.
`FinishedAt`	DATETIME	Date/time when the task finished (Done, Failed or Cancelled).

Event callbacks

Property	Type	Description
`OnComplete`	STRING	Name of procedure to invoke when Status moves to Done.
`OnFailed`	STRING	Name of procedure to invoke when Status moves to Failed.
`OnProgress`	STRING	Name of procedure to invoke each time Progress changes.

Task procedure signature

Every procedure that runs as a task must accept exactly these two parameters.

PROCEDURE MyTask(loParams AS OBJECT, loTask AS OBJECT)
    * loParams -- data passed from Run() by the caller
    * loTask   -- the Task object: set Progress and Result here
    loTask.Progress = 50
    loTask.Result   = "my result value"
ENDPROC

Status lifecycle

A Task advances through the following states:

[Pending] -> [Running] -> [Done]
                      \-> [Failed]
                      \-> [Cancelled]

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