Qt ActiveX dynamicCall: bad parameter count

问题

I am trying to use an ActiveX control in my program.

QAxWidget* mAX = new QAxWidget();
mAX->setControl("{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}");

I know that there is a function:

put_ChannelType(long newValue)

But when I try to execute it:

mAX->dynamicCall("put_ChannelType(long)",2);
mAX->dynamicCall("put_ChannelType(int)",2);
mAX->dynamicCall("put_ChannelType(long)",QVariant(2));
mAX->dynamicCall("put_ChannelType(int)",QVariant(2));

I get:

QAxBase: Error calling IDispatch member put_ChannelType: Bad parameter count

Any idea what is going wrong ?

EDIT:

Weird thing is if I call

mAX->dynamicCall("put_ChannelType()");

I do not get any error message...

EDIT 2:

This also fails (as Constantin suggested)

QList<QVariant> varlist;
varlist << (int)1;
mAX->dynamicCall("put_ChannelType(int)",varlist);

回答1:

Got this solved using the generateDocumentation() function.

I was using this ActiveX control in another application, but an MFC one.

It seems the function names I was referring to (which were in a machine generated IDispatch wrapper class created by VS) were not the same as the ones Qt listed.

i.e. put_ChannelType is actually SetChannelType...

Maybe this is just a version issue ?

Anyways, important part is knowing that generateDocumentation() can list you all the functions you can call with dynamicCall.

回答2:

Is it OK? mAX->dynamicCall("put_ChannelType(const QVariant &)", (long)2);

来源：https://stackoverflow.com/questions/14859552/qt-activex-dynamiccall-bad-parameter-count