External API

What is external API?

External API is library defined typically for external usage, which means to produce JC4XL document silently by a service in the background, or interactively attach to running Excel instances and extend the sheets with JC4XL structures from a different desktop application.

How to access it?

•	From VBA, add the reference from Tools/Reference

AvailableRef.ExternalAPI (1.1 Type Library from JC4XL 1.1.4)

•	From C++, add the references into your stdafx.h module

#import "libid:2D09FA5A-9FD9-46E6-A4E3-3327BF6E48EB" raw_interfaces_only named_guids

using namespace JChemExcelCOMInterfacesLib;

#import "libid:3ADEBF5E-5174-42B9-9EA4-C7FB03B2C427" raw_interfaces_only named_guids

using namespace JChemExcelAPILib;

and compile stdafx.cpp afterwards.

•	From C# project, add the references of the delivered interop assembly modules to your project

Form.SolutionExplorer.ExternalAPI

or browse the COM library similarly how it was described in the first point (VBA)

Helper functions in External API library

The library contains several functions, properties defined on ExternalAPI COM object to help you access the running JC4XL instances and provide some additional routine prior to using the real API calls (see API Interface section above). Helpers are useful since not necessary to include Excel reference to operate with API routines. (Available versions are 1.0 and 1.1).

Function/Property Name	Parameters	Optional	Type in COM	Type in VBA	Type in C#/Java
DefaultFileExtension (property) (1.0)	Return value (determines the installed Excel version and its default file extension for generating file name from the host application)		BSTR*	string	string
ActiveInstance (property) (1.0)	newVal (new active instance id the API calls will be affected)	N	BSTR	string	string
	Return value		BSTR*	string	string
KeepInstanceAlive (property) (1.0)	newVal (this is when creating a new workbook, after creation it should be displayed and kept open)	N	VARIANT_BOOL	boolean	boolean
	Return value		VARIANT_BOOL*	boolean	boolean
GetInstanceIds (1.0)	Return value (gives back all running instances)		SAFEARRAY(BSTR)*	Dim () as string	string[]
GetWorkbooks (1.0)	Return value (gives back all workbooks belonging to the active instance)		SAFEARRAY(BSTR)*	Dim () as string	string[]
GetWorksheets (1.0)	workbookId (workbook name in the active instance)	N	BSTR	string	string
	Return value (gives back all worksheets belonging to the active instance and the specified workbook id)		SAFEARRAY(BSTR)*	Dim () as string	string[]
GetInstanceDisplayName (1.0)	instanceId	N	BSTR	string	string
	Return value (display name for the specified instance id)		BSTR*	string	string

Before calling any of main API functions the active instance should be set on the External API object. Available Excel and JC4XL plug-in instances can be retrieved by calling GetInstanceIds function. Instance id list includes the „New Instance” constant as well for creating new hidden or visible JC4XL workbook instances (for JC4XL document service purposes).

How to instantiate External API?

•

From VBA

Dim api As JChemExcelAPILib.ExternalAPI
Set api = New JChemExcelAPILib.ExternalAPI

•

From C#

private var api = new JChemExcelAPILib.ExternalAPIClass();

•

From C++

JChemExcelAPILib::IExternalAPIPtr api;
api.CreateInstance(JChemExcelAPILib::CLSID_ExternalAPI);

api.CreateInstance(__uuidof(JChemExcelAPILib::ExternalAPI));

Back to index page

Do you have a question? Would you like to learn more? Please browse among the related topics on our support forum or search the website. If you want to suggest modifications or improvements to our documentation email our support directly!