我已经浪费了大约 6 个小时，试图按照网上的各种说明让 MySQL 与 Qt 一起工作。我现在想割腕!

有没有人对如何在 Qt 中安装 QMYSQL 驱动程序有简单和详细的解释？

我有 Mac 10.6，我是初学者 n00b。

我将衷心感谢您的帮助!

萨那。

编辑:

当我执行 grep 时，我得到了以下文件，所以在这些文件中，我只是为了好玩，将 libqsqlmysql.dylib 复制到所有文件夹中，但我仍然无法编译...我收到一条错误消息说 QSqlDatabase:未加载 QMYSQL 驱动程序

/Library/Application Support/DivX/QtPlugins/sqldrivers/libqsqlite.dylib 
/Users/pfn368/QtSDK/Assistant.app/Contents/PlugIns/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Designer.app/Contents/PlugIns/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Desktop/Qt/4.8.0/gcc/plugins/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Desktop/Qt/4.8.0/gcc/plugins/sqldrivers/libqsqlite_debug.dylib
/Users/pfn368/QtSDK/Desktop/Qt/474/gcc/plugins/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Desktop/Qt/474/gcc/plugins/sqldrivers/libqsqlite_debug.dylib
/Users/pfn368/QtSDK/Madde/sysroots/harmattan-arm-sysroot/usr/lib/qt4/plugins/sqldrivers/libqsqlite.so
/Users/pfn368/QtSDK/Madde/sysroots/harmattan-nokia-arm-sysroot/usr/lib/qt4/plugins/sqldrivers/libqsqlite.so
/Users/pfn368/QtSDK/Maemo/4.6.2/sysroots/fremantle-arm-sysroot-20.2010.36-2-slim/usr/lib/qt4/plugins/sqldrivers/libqsqlite.so
/Users/pfn368/QtSDK/Qt Creator.app/Contents/MacOS/qmlpuppet.app/Contents/PlugIns/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Qt Creator.app/Contents/PlugIns/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/QtSources/4.8.0/plugins/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/QtSources/4.8.0/plugins/sqldrivers/libqsqlite_debug.dylib
/Users/pfn368/QtSDK/Simulator/Application/simulator.app/Contents/PlugIns/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Simulator/Qt/gcc/plugins/sqldrivers/libqsqlite.dylib
/Users/pfn368/QtSDK/Simulator/Qt/gcc/plugins/sqldrivers/libqsqlite_debug.dylib

这是我的 .pro 文件

QT       += sql core gui\
           network

TARGET = mini-stock-exchange
TEMPLATE = app

SOURCES += ./src/main.cpp\
        ./src/mainwindow.cpp

HEADERS  += ./header/mainwindow.h

FORMS    += ./ui/mainwindow.ui

我的包括

#include "./header/mainwindow.h"
#include "ui_mainwindow.h"
#include <QtSql/QSqlDatabase>
#include <QtSql/QSqlQuery>
#include <QFile>
#include <QtSql/QSqlError>
#include <qsqldatabase.h>
#include <QtCore>
#include <QtSql>

调用数据库的代码

QSqlDatabase defaultDB = QSqlDatabase::addDatabase("QMYSQL3");
if ( !defaultDB.isValid() ) {
    qWarning( "Failed to connect to the database driver" );
}
defaultDB.setDatabaseName( "nicu" );
defaultDB.setUserName( "root" );
defaultDB.setPassword( "root" );
defaultDB.setHostName( "http://localhost:8889" );

最佳答案

首先下载Qt SDK源码和一个版本的mysql服务器源码，将它们都解压。

创建指向 MySQL 的 lib 文件的符号链接(symbolic link):

sudo ln -s /Users/simon/Downloads/mysql-5.6.11-osx10.7-x86_64/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.dylib
sudo ln -s /Users/simon/Downloads/mysql-5.6.11-osx10.7-x86_64/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient_r.dylib
sudo ln -s /Users/simon/Downloads/mysql-5.6.11-osx10.7-x86_64/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.18.dylib
sudo ln -s /Users/simon/Downloads/mysql-5.6.11-osx10.7-x86_64/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient_r.18.dylib

之后 cd 将您提取的 Qt SDK 放入文件夹 /Users/simon/Downloads/qt-everywhere-opensource-src-4.8.4/src/plugins/sqldrivers/mysql

构建库:

qmake -spec macx-g++ -o Makefile "INCLUDEPATH+=/Users/simon/Downloads/mysql-5.6.11-osx10.7-x86_64/include" "LIBS+=-L/usr/lib -lmysqlclient_r" mysql.pro
make
mv libqsqlmysql_debug.dylib libqsqlmysql.dylib
cp -R libqsqlmysql.dylib /Developer/Applications/Qt/plugins/sqldrivers/

之后你应该可以使用 QMYSQL 插件了。使用这行代码检查库是否正确加载(将它放在一些构造函数中，以便在启动应用程序后立即输出):

qDebug() << QCoreApplication::libraryPaths();
qDebug() << QSqlDatabase::drivers();

例如我的输出现在看起来像这样:

("/Developer/Applications/Qt/plugins", "/Users/simon/Coding/qt4c/build-SQLtable-Desktop-Debug/SQLtable.app/Contents/MacOS") 
("QSQLITE", "QMYSQL3", "QMYSQL", "QODBC3", "QODBC", "QPSQL7", "QPSQL") 

关于用于 Mac 上 Qt 的 MySQL，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/7579212/