Qt共享库、静态库、Qt Plugin的创建和加载。

Qt新建文件或项目，选择Library,选择C++库，选择共享库，代码如下：

//.h

#ifndef MYSHAREDLIBRARY_H

#define MYSHAREDLIBRARY_H

#include "mysharedlibrary_global.h"

class MYSHAREDLIBRARYSHARED_EXPORT MySharedLibrary

public:

    MySharedLibrary();

    int sum(int a, int b);

};

int MYSHAREDLIBRARYSHARED_EXPORT sum(int a, int b);

#endif // MYSHAREDLIBRARY_H

//.cpp

#include "mysharedlibrary.h"

MySharedLibrary::MySharedLibrary()

int MySharedLibrary::sum(int a, int b)

    return a+b;

int sum(int a, int b)

    return a+b;

Qt新建文件或项目，选择Library,选择C++库，选择静态链接库，代码如下：

//.h

#ifndef STATICLIBRARY_H

#define STATICLIBRARY_H

class StaticLibrary

public:

    StaticLibrary();

    int sum(int a, int b);

};

int sum1(int a, int b);

#endif // STATICLIBRARY_H

//.cpp

#include "staticlibrary.h"

StaticLibrary::StaticLibrary()

int StaticLibrary::sum(int a, int b)

    return a+b;

int sum1(int a, int b)

    return a+b;

//接口编写

#ifndef MYINTERFACETEST_H

#define MYINTERFACETEST_H

#include <QObject>

#include <QString>

class MyInterfaceTest: public QObject

{

Q_OBJECT

public:

MyInterfaceTest(QObject *parent = 0):QObject(parent) {}

virtual ~MyInterfaceTest() {}

virtual QString filters() const = 0;

virtual int loader() const = 0;

};

Q_DECLARE_INTERFACE(MyInterfaceTest, “com.mashijie.interface”)

#endif // MYINTERFACETEST_H

//创建插件

//.h

#ifndef GENERICPLUGIN_H

#define GENERICPLUGIN_H

#include <QGenericPlugin>

#include <myinterfacetest.h>

class GenericPlugin : public MyInterfaceTest

    Q_OBJECT

#if QT_VERSION >= 0x050000

    Q_PLUGIN_METADATA(IID "com.mashijie.interface" FILE "QtPluginTest.json")

#endif // QT_VERSION >= 0x050000

    Q_INTERFACES(MyInterfaceTest)

public:

    GenericPlugin(QObject *parent = 0);

    virtual QString filters() const;

    virtual int loader() const;

};

#endif // GENERICPLUGIN_H

//.cpp

#include "genericplugin.h"

GenericPlugin::GenericPlugin(QObject *parent) :

    MyInterfaceTest(parent)

QString GenericPlugin::filters() const

    return QString("ddd");

int GenericPlugin::loader() const

    return 2;

#if QT_VERSION < 0x050000

Q_EXPORT_PLUGIN2(QtPluginTest, GenericPlugin)

#endif // QT_VERSION < 0x050000

//.main

#include <QCoreApplication>

#include <QDebug>

#include <mysharedlibrary.h>

#include <staticlibrary.h>

#include <QDir>

#include <QPluginLoader>

int main(int argc, char *argv[])

    QCoreApplication a(argc, argv);

qDebug() << sum(1, 4);

//共享库调用，编译需要头文件和lib，运行时需要dll

    MySharedLibrary mySharedLibrary;

    qDebug() << mySharedLibrary.sum(1,2);

    qDebug() << sum1(1, 6);

//静态链接库调用，只需要编译即可，需要头文件和lib

    StaticLibrary staticLibrary;

    qDebug() << staticLibrary.sum(1,2);

    //插件加载，把插件生成的dll放在指定目录下即可

    QDir pluginsDir(qApp->applicationDirPath());

    pluginsDir.cd("plugins");

    foreach (QString fileName, pluginsDir.entryList(QStringList() << "*.dll", QDir::Files))

        QPluginLoader *loader = new QPluginLoader(pluginsDir.absoluteFilePath(fileName));

        QObject *plugin = loader->instance();

        qDebug() << fileName;

    return a.exec();