[python-win32] comtypes: Problem with passing string argument

[Einar Sørheim]

Thomas Heller wrote:

>Einar Sørheim schrieb:
>  
>
>>I have a com library that I have a hard time getting to work, some of it 
>>works in win32com, some in comtypes.
>>Have a question first for comtypes(using python2.4 and svn checkout 
>>3.jan07 of comtypes):
>>The following code fails at the last step:
>>        self.dl = comtypes.client.GetModule(r"C:\Program Files\Common 
>>Files\Calsep\PvtsDataLayer.dll")
>>        self.fl = comtypes.client.GetModule(r"C:\Program Files\Common 
>>Files\Calsep\PvtsDataModel.dll")
>>        self.datalayer = 
>>comtypes.client.CreateObject(self.dl.FluidDepoWaxDataLayer)
>>        self.fluid = comtypes.client.CreateObject(self.fl.Fluid)
>>        cp=self.datalayer.CheckCompatibility(DatabasePath=r"C:\Program 
>>Files\Calsep\Sample Programs\FlashOSDatabase.fdb")
>>Errormessage:
>>  File "mtucpvt.py", line 46, in Connect
>>    cp=self.datalayer.CheckCompatibility(DatabasePath=r"C:\Program 
>>Files\Calsep\Sample Programs\FlashOSDatabase.fdb")
>>ValueError: Procedure probably called with too many arguments (4 bytes 
>>in excess)
>>
>>The generated inteface code looks like:
>>_FluidDepoWaxDataLayer._methods_ = [
>>    COMMETHOD([dispid(1745027104), 'propput'], HRESULT, 'UseDatabaseFormat',
>>              ( ['in'], PvtsDLUseDatabaseFormat, 'None' )),
>>    COMMETHOD([dispid(1745027104), 'propget'], HRESULT, 'UseDatabaseFormat',
>>              ( ['retval', 'out'], POINTER(PvtsDLUseDatabaseFormat), 
>>'None' )),
>>    COMMETHOD([dispid(1610809375)], HRESULT, 'IsConnectedAsReadOnly',
>>              ( ['retval', 'out'], POINTER(VARIANT_BOOL), 'None' )),
>>    COMMETHOD([dispid(1610809374)], HRESULT, 'CheckCompatibility',
>>              ( ['in'], BSTR, 'DatabasePath' ),
>>              ( ['retval', 'out'], POINTER(c_short), 'None' )),
>>
>>Any ideas on what is wrong here?
>>    
>>
>
>This looks like some problem with the interface code.  Was it generated or
>written manually?  Does (re-)generating the module help?  Are you sure
>that the type library is up-to-date?
>
>If you also have problems using the object in win32com, what are the symptoms?
>
>Thomas
>  
>
Interface code was generated automatically, deleting the files in the 
'gen' folder and re-generating the interface files does not help.
win32com works as expected on this part of the code, their interface 
code looks like the following:
class _FluidDepoWaxDataLayer(DispatchBaseClass):
    CLSID = IID('{FF3D17D3-69D4-4BC9-8173-7BDBBDDC4FE3}')
    coclass_clsid = IID('{F6A1D76E-C0AF-4A99-9D35-DDE8C3DF1B3A}')

    def AddDepoWaxCase(self, DepoWaxCase=defaultNamedNotOptArg):
        return self._ApplyTypes_(1610809367, 1, (3, 0), ((16393, 3),), 
'AddDepoWaxCase', None,DepoWaxCase
            )

    def AddFluid(self, Fluid=defaultNamedNotOptArg):
        return self._ApplyTypes_(1610809358, 1, (3, 0), ((16393, 3),), 
'AddFluid', None,Fluid
            )

    def CheckCompatibility(self, DatabasePath=defaultNamedNotOptArg):
        return self._oleobj_.InvokeTypes(1610809374, LCID, 1, (2, 0), 
((8, 1),),DatabasePath
            )
......
vtables entry is :
    (( 'CheckCompatibility' , 'DatabasePath' , None , ), 1610809374, 
(1610809374, (), [ (8, 1, None, None) ,
            (16386, 10, None, None) , ], 1 , 1 , 4 , 0 , 148 , (3, 0, 
None, None) , 0 , )),

However win32com fails at a later stage using a companion com library, I 
will make a separate post about this problem.
thanks,
Einar Sørheim