How to work with a COM Object

[cpgood]

NOTE: This post was originally posted in the wrong forum. It is being posted here, under desktop applications, which is the correct location:

I need help knowing what tools to use in A5v9 to work with a COM Object. The COM Object has about 25 different functions that can be called and in some cases results returned. I just simply do not know where to start with A5's tools to work with a COM Object. Once I understand what tools to look at I feel that I would be in good shape. I have excellent documentation for the COM Object and all of its functions.

Thanks in advance for any one's help!

CP Good

[Finian Lennon]

Re: How to work with a COM Object

Hi:

This is what worked for me - even in A5V5 - to connect with an in-house COM object written to provide an interface for communications with an online medical service. The file object was a dll called, for example, WebLinkClient.dll

1. Make sure that file is in a known locatiion
2. Register the file from that location using RegSvr32.
3. You may need to reboot the machine so that you can open the Ole Automation Browser in A5, where the object you registered should appear in the list of scriptable objects. This will tell you (if the documentation for the COM object does not) how to refer to the object when you connect.
4. Create a connection to the file using something like:

weblink = Ole.create("PWorks.services.Weblink")
webconnect = weblink.Connect(rtsid,rtspass)			'0 indicates a connection
if webconnect <> 0 then
	ui_Msg_box("",weblink.GetLastErrorMsg(),ui_attention_symbol)
		save_to_file(weblink.GetLastErrorMsg(),RTSCommdir + "Error_connect.txt")
	 	 	weblink.disconnect()
	 			EC_CheckElig = .F.
					goto EC_CheckElig_Finish
end if

In the above code the idea is to create an object pointer, "Weblink" that we can use to communicate with the COM object and access its methods and properties. Everything after that, such as variables passed into its functions, is unique to the COM object I was working with.

If the connection succeeds then you can do calls to the object like:

webconnect = weblink.Connect(rtsid,rtspass)			'0 indicates a connection
if webconnect <> 0 then
     ui_Msg_box("",weblink.GetLastErrorMsg(),ui_attention_symbol)
	save_to_file(weblink.GetLastErrorMsg(),RTSCommdir + "Error_connect.txt")
		weblink.disconnect()
			EC_CheckElig = .F.
			goto EC_CheckElig_Finish
end if

'elig_sub_file was an XML file created according to the specifications of the COM file which passed patient and insurance parameters
'to the query function and asked for a return value about the patient's coverage in html format in the file elig_resp_file
'if the call was successfule, the response file elig_resp_file was passed to IE for the user to view onscreen.

webquery = Weblink.RunQuery2("XML",elig_sub_file,"HTML",elig_resp_file)
	if webquery <> 0 then
 		 ui_Msg_box("",weblink.GetLastErrorMsg(),ui_attention_symbol)
			save_to_file(weblink.GetLastErrorMsg(),RTScommdir + "Error_Query.txt")
	  		 	weblink.disconnect()
   					EC_CheckElig = .F.
   						goto EC_CheckElig_Finish
	end if

	Webdisc = weblink.disconnect()

	if Webdisc <> 0 then
	  ui_Msg_box("",weblink.GetLastErrorMsg(),ui_attention_symbol)
	  	EC_CheckElig = .F.
	  		goto EC_CheckElig_Finish
			else			'disconnect OK
		  	dim ie as p
				ie = Ole.Create("InternetExplorer.Application")
				ie.navigate(elig_resp_file,1)
				ie.offline = .T.
				ie.theatermode = .F.
				ie.menubar = .F.
				ie.toolbar = .F.
				ie.addressbar = .F.
				ie.visible = .T.
				ie.refresh()
				EC_CheckElig = .T.
					goto EC_CheckElig_Finish
	end if

There was a lot of other code (probably hundreds of lines) surrounding the calls to the com object

Every situation is different but this approach should still work.

[cpgood]

Re: How to work with a COM Object

Hi Finian,

Thank you for the extensive reply. I know it takes a lot of time to do this and I appreciate your super help. I will study your reply and implement.

Thank you again.

CP Good

[fsi]

Re: How to work with a COM Object

I see the object's Properties and Methods are exposed.
But how does one gain access to the object's events in this scenario (of object instantiation via "ole.create")?