How to Call .dll from Qt5.4

[binary001]

Hello,

I started a project call dll from Qt C++.

#-------------------------------------------------
#
# Project created by Qt5.4 at Windows 7 32bit
#
#-------------------------------------------------
 
QT       += core
QT       -= gui
 
TARGET = CallDll
CONFIG   += console
CONFIG   -= app_bundle
 
TEMPLATE = app
 
 
SOURCES += main.cpp
LIBS += "C:/Qt-Lessons/CallDll/libzinnia.dll"
 
HEADERS += \
    zinnia.h

#-------------------------------------------------
#
# Project created by Qt5.4 at Windows 7 32bit
#
#-------------------------------------------------

QT       += core
QT       -= gui

TARGET = CallDll
CONFIG   += console
CONFIG   -= app_bundle

TEMPLATE = app


SOURCES += main.cpp
LIBS += "C:/Qt-Lessons/CallDll/libzinnia.dll"

HEADERS += \
    zinnia.h

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#include <QCoreApplication>
#include <QDebug>
#include "zinnia.h"
 
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
 
    zinnia::Recognizer *recognizer = zinnia::Recognizer::create();
      if (!recognizer->open("c:/handwriting-zh_CN.model")) {
        qDebug() << recognizer->what();
 
      }
 
    return a.exec();
}

#include <QCoreApplication>
#include <QDebug>
#include "zinnia.h"

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    zinnia::Recognizer *recognizer = zinnia::Recognizer::create();
      if (!recognizer->open("c:/handwriting-zh_CN.model")) {
        qDebug() << recognizer->what();

      }

    return a.exec();
}

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I also copied libzinnia.dll to my project, debug, release folders and add LIBS in .pro file

But when I build project, compiler gave errors :
undefined reference to ..........

How can I fix it?

Thanks

[anda_skoa]

Try to give the path and the name of the library separately

LIBS += -L C:/Qt-Lessons/CallDll -llibzinnia

LIBS += -L C:/Qt-Lessons/CallDll -llibzinnia

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Cheers,
_

[binary001]

Thank anda_skoa for your reply.

But it gives same error. undefined reference to `_imp___ZN6zinnia9Character6createEv'
I found a project. It's at Linux and Qt 5.1

LIBS += -L/home/AAbin/source/project -lzinnia

It used -lzinnia, not -llibzinnia. Is it depend upon dll' file name? or because of different Qt version.
I think I must put l prefix for dll file name.

I did not build the dll myself, I got it from http://zinnia.sourceforge.net/ that I am trying to use into my application.
I used it Qt Creator 3.3.0 and Qt5.4. and mingw491_32.

How can I fix it. DLL file name is libzinnia.dll.

I changed and tested many words. But it's not successful. I used at Windows 7

LIBS += -L c:/project -llibzinnia

or

LIBS += "c:/project/libzinnia.dll"

LIBS += "c:\project\libzinnia.dll"

Thanks.

[anda_skoa]

It used -lzinnia, not -llibzinnia. Is it depend upon dll' file name? or because of different Qt version.

On Linux the lib name is prefixed with "lib" by the compiler, I am pretty sure it isn't on Windows.

I think I must put l prefix for dll file name.

I did not build the dll myself, I got it from http://zinnia.sourceforge.net/ that I am trying to use into my application.
I used it Qt Creator 3.3.0 and Qt5.4. and mingw491_32.

You could try building it yourself, it might have been built with a different, incompatible, compiler.

Cheers,
_