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Title: I created a sample class, but its full of errors - so here are questions:
Post by: Murray Ruggiero on January 03, 2011, 05:27:18 PM

Here is a fragment of some code I wrote. It is full of errors. If anyone can explains some or all of them, that would be great:

#COMPILE EXE
#DIM ALL

#INCLUDE ONCE "WIN32API.INC" ' include windows api calls
MACRO BOOLEAN = INTEGER
MACRO TRUE = -1
MACRO FALSE = 0

$MyClassGuid = "{2e4ff4cf-776c-4bb4-bef5-1daad3362511}"
$MyInterfaceGuid = "{243c8ee5-35ae-4c17-a4d8-a2952cdcac3c}"

CLASS c_ClassTryTranslatingThis $MyClassGuid as COM
INTERFACE i_ClassTryTranslatingThis $MyInterfaceGuid
INHERIT AUTOMATION

LETS STOP HERE, I ALREADY GET AN ERROR: WHICH IS:
' CLASS c_ClassTryTranslatingThis $MyClassGuid AS COM - invalid string length !
APPARENTLY THERE IS SOMETHING WRONG WITH THE GUID STRING

NOW LETS CONTINUE:
Private Type myStructTypeWithString
strfield As String
intField As Integer
End Type
THE ABOVE IS REJECTED.
SO I GET RID OF THE 'PRIVATE' PREFIX AND GET ANOTHER ERROR: 'ERROR 476 : Block/scanned statements NOT allowed here

ALSO: CONSTANTS CANNOT BE DECLARED WITHIN THE CLASS - I GET AN ERROR FOR THAT.

ALSO, THE FOLLOWING LINE IS REJECTED:
METHOD getCurrency() PRIVATE As Currency
AS IS THIS ONE:
MsgBox EXE & Str$(59.7)

Basically, I want to create a class that can be used as a com object from other classes, and I want the other classes to be able to pass UDTs (user-defined-types) to the METHOD, and the logical place to define those UDTs seems to be in the class, and I want some methods to be PRIVATE (but the private keyword above did not work) and others EXPORT.
Any advice is appreciated.

Title: Re: I created a sample class, but its full of errors - so here are questions:
Post by: Edwin Knoppert on January 03, 2011, 06:31:53 PM

I am sure the help can, seems you totally avoided the help to learn some syntax and dumped some vb code in your editor?

Title: Re: I created a sample class, but its full of errors - so here are questions:
Post by: José Roca on January 03, 2011, 06:42:23 PM

Yes, it looks VB-like code.

Quote
LETS STOP HERE, I ALREADY GET AN ERROR: WHICH IS:
' CLASS c_ClassTryTranslatingThis $MyClassGuid AS COM - invalid string length !
APPARENTLY THERE IS SOMETHING WRONG WITH THE GUID STRING

They must defined as:

$MyClassGuid = GUID$("{2e4ff4cf-776c-4bb4-bef5-1daad3362511}")
$MyInterfaceGuid = GUID$("{243c8ee5-35ae-4c17-a4d8-a2952cdcac3c}")

Quote
SO I GET RID OF THE 'PRIVATE' PREFIX AND GET ANOTHER ERROR: 'ERROR 476 : Block/scanned statements NOT allowed here

You can't use dynamic strings in an structure. You have to change strfield As String to strfield As String * number of characters.

Quote
ALSO, THE FOLLOWING LINE IS REJECTED:
METHOD getCurrency() PRIVATE As Currency

Remove PRIVATE.

Quote
AS IS THIS ONE:
MsgBox EXE & Str$(59.7)

Change it to MsgBox EXE.PATH$ & Str$(59.7)

Title: Re: I created a sample class, but its full of errors - so here are questions:
Post by: Peter Weis on January 03, 2011, 07:19:06 PM

Hi Murray,
Look at the power basic assistance. It may help you further. You wanted a private method. A CLASS method is private

Quote
What is a Class Method?
A CLASS METHOD is one which is private to the class in which it is located. That is, it may only be called from a METHOD or PROPERTY in the same class. It is invisible elsewhere. The CLASS METHOD must be located within a CLASS block, but outside of any INTERFACE blocks. This shows it is a direct member of the class, rather than a member of an interface.

CLASS MyClass
INSTANCE MyVar AS LONG

CLASS METHOD MyClassMethod(BYVAL param AS LONG) AS STRING
METHOD = "My" + STR$(param + MyVar)
END METHOD

INTERFACE MyInterface
INHERIT IUNKNOWN
METHOD MyMethod()
Result$ = ME.MyClassMethod(66)
END METHOD
END INTERFACE
END CLASS

Regards Peter

Title: Re: I created a sample class, but its full of errors - so here are questions:
Post by: Edwin Knoppert on January 03, 2011, 10:38:34 PM

Don't forget the hidden feature to hide a whole interface.
ActiveX allows you to have multiple interfaces in a single class.

Theos PowerBasic Museum 2017

Archive => Discussion - Legacy Software (PBWIN 9.0+/PBCC 5.0+) => Topic started by: Murray Ruggiero on January 03, 2011, 05:27:18 PM