an own dll for liberty basic. >>> hello ,is ok.

[held12345]

Hi good afternoon.

how do you create your own dll for liberty basic?

this is what a cdll looks like for me.
Pass 2 values then multiply and output again.

lbb_dll.dll :

------------------------

ProcedureCDLL.l mult(a.l,b.l)
wertl.l = a*b
ProcedureReturn wertl.l
EndProcedure

ProcedureCDLL.l div(a.l,b.l)
wertl.l = a/b
ProcedureReturn wertl.l
EndProcedure

ProcedureCDLL.d multf(a.d,b.d)
wertl.d = a*b
ProcedureReturn wertl.d
EndProcedure

ProcedureCDLL.d divf(a.d,b.d)
wertl.d = a/b
ProcedureReturn wertl.d
EndProcedure

------------------------

how does the reception pleace of liberty basic look like and the value for printing.

thanks

greeting


OPEN "lbb_dll.dll" for dll as #handle

x=6789
y=107
calldll #handle, "mult" , x as long, y as long , erg as long
print(erg)

x=erg
y=107
calldll #handle, "div" , x as long, y as long , erg as long
print(erg)

print

x=2.578
y=222.532
calldll #handle, "multf" , x as double, y as double , erg as double
print(erg)

x=erg
y=222.532
calldll #handle, "divf" , x as double, y as double , erg as double
print(erg)


wait

Attachments:

[Brandon Parker]

Just a word of caution, be careful sending "Double" values from LB to DLLs. You should force each value to actually be a Double prior to sending it. For instance, if your multiplication method in the DLL multiplies two numbers together such as "2.0" and "2.0" together then the result returned by the DLL will be the Double of that multiplication which would be "4.0", but when LB retrieves that value, it will automatically turn it into an integer "4". This is just how LB works... You will need to re-force the value back to a Double.

Here are the functions I use to force variables to be floating-point...
Open "lbb_dll.dll" For DLL As #myDLL

x=200.0
y=2.0
CallDLL #myDLL, "multf", x As double, y As double , erg As double
print erg

x= Val(ConvertToDouble$(erg,1,5))
y=2.0
CallDLL #myDLL, "divf", x As double, y As double , erg As double
print erg

Close #myDLL

'____________________________________________________________________________________________________________________
'____________________________________________________________________________________________________________________

   Function ConvertToDouble$(value, integerPart, decimalPart)
       'integerPart does not Limit the integer portion; included for future Limit functionality
       integerPart$ = string$("#", integerPart)
       decimalPart$ = string$("#", decimalPart)
       ConvertToDouble$ = Trim$(RemChar$(Using(integerPart$;".";decimalPart$, value), "%"))
   End Function

'____________________________________________________________________________________________________________________
'____________________________________________________________________________________________________________________

   Function string$(myString$, numstring)
       For i = 1 To numstring
           string$ = string$ + myString$
       Next i
   End Function

One interesting thing for me here is that you have used "Print(erg)" in your code and it seems to work for printing to the MainWin on LB 4.5.1. I do not recall coming across this previously although I could be simply not remembering it. While this "Print(value)" form is not documented in the helpfile, it does seem to work, and so does "Print (value)" as well...


{:0)

Brandon Parker

[held12345]

hello thanks for help.

here one error :

convertToDouble$ = Trim$(RemChar$(Using(integerPart$;".";decimalPart$, value), "%"))

liberty basic : 4.5.0

greeeting

Attachments:

[Brandon Parker]

Did you not copy the string$() function into the code base?

   Function string$(myString$, numstring)
       For i = 1 To numstring
           string$ = string$ + myString$
       Next i
   End Function


{:0)

Brandon Parker

[held12345]

this is the error:
convertToDouble$ = Trim$(RemChar$(Using(integerPart$;".";decimalPart$, value), "%"))

Open "lbb_dll.dll" For DLL As #myDLL

x=200.0
y=2.0
CallDLL #myDLL, "multf", x As double, y As double , erg As double
print erg

x= Val(ConvertToDouble$(erg,1,5))
y=2.0
CallDLL #myDLL, "divf", x As double, y As double , erg As double
print erg


wait
Function ConvertToDouble$(value, integerPart, decimalPart)
  'integerPart does not Limit the integer portion; included for future Limit functionality
   integerPart$ = string$("#", integerPart)
   decimalPart$ = string$("#", decimalPart)
   convertToDouble$ = Trim$(RemChar$(Using(integerPart$;".";decimalPart$, value), "%"))
End Function

Function string$(myString$, numstring)
  For i = 1 To numstring
     string$ = string$ + myString$
  Next i
End Function

[Brandon Parker]

I see...

It appears that the variable return within the function has been changed. It should be "ConvertToDouble$" and NOT "convertToDouble$" as the return variable since the name of the function is thus. The example I provided above has it correct, so there must have been something changed on your end. Just capitalize the "C" in "ConvertToDouble$" and it should work.


{:0)

Brandon Parker

[held12345]

is error.

Open "lbb_dll.dll" For DLL As #myDLL

x=200.0
y=2.0
CallDLL #myDLL, "multf", x As double, y As double , erg As double
print erg

x= Val(ConvertToDouble$(erg,1,5))
y=2.0
CallDLL #myDLL, "divf", x As double, y As double , erg As double
print erg

Close #myDLL

'____________________________________________________________________________________________________________________
'____________________________________________________________________________________________________________________

   Function ConvertToDouble$(value, integerPart, decimalPart)
       'integerPart does not Limit the integer portion; included for future Limit functionality
       integerPart$ = string$("#", integerPart)
       decimalPart$ = string$("#", decimalPart)
       ConvertToDouble$ = Trim$(RemChar$(Using(integerPart$;".";decimalPart$, value), "%"))
   End Function

'____________________________________________________________________________________________________________________
'____________________________________________________________________________________________________________________

   Function string$(myString$, numstring)
       For i = 1 To numstring
           string$ = string$ + myString$
       Next i
   End Function

greeting