QT4.8.5 connect to the database (read and write data) and qt4.8.5 read and write

QT4.8.5 connect to the database (read and write data) and qt4.8.5 read and write

#include "mainwindow.h"

#include <QApplication>

#include <QLabel>

#include <QPushButton>

#include <QtCore/QCoreApplication>

#include <QCoreApplication>

#include <QSpinBox>

#include <QSlider>

#include <QHBoxLayout>

#include  <QFile>

#include <QFileInfo>

#include <QDebug>

#include "newspaper.h"

#include "reader.h"

#include <QtSql>

#include <QSqlQuery>

#include <QMessageBox>

#include <QSqlError>

#include <QTextCodec>

bool connect(const QString &dbName)

{

    QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");

    db.setHostName("localhost");

    db.setDatabaseName(dbName);

    db.setPort(3306);

    db.setUserName("root");

    db.setPassword("root");

    if (!db.open())

    {

        QMessageBox::critical(0, QObject::tr("Database Error"), db.lastError().text());

        return false;

    }

    else

    {

QMessageBox: information (0, QObject: tr ("Tips"), QObject: tr ("connection successful ..! "));

        return true;

    }

}

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

{

    QApplication a(argc, argv);

/* Test the connected database

// Test the supported Databases

    //    QCoreApplication a(argc, argv);

    //        qDebug() << "Available drivers:";

    //        QStringList drivers = QSqlDatabase::drivers();

    //        foreach(QString driver, drivers)

    //        qDebug() << "\t "<< driver;

    //        qDebug() << "End";

    //    return a.exec();

// Test to open the database

    //    QCoreApplication a(argc, argv);

    //           QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");

    //           db.setHostName("localhost");

// Db. setDatabaseName ("qttest"); // name of the created database

// Db. setUserName ("root"); // User Name

// Db. setPassword ("root"); // Password

// Bool OK = db. open (); // If OK is set to true, otherwise false

    //           qDebug() << "\t"<<ok;

    qDebug() << "Available drivers:";

        QStringList drivers = QSqlDatabase::drivers();

        foreach(QString driver, drivers)           qDebug() << "\t "<< driver;

        qDebug() << "End";

    */

// Test the connection and open the operation Database

    QTextCodec *codec = QTextCodec::codecForName("utf-8");

    QTextCodec::setCodecForLocale(codec);

    QTextCodec::setCodecForCStrings(codec);

    QTextCodec::setCodecForTr(codec);

    if (connect("eng"))

    {

        QSqlQuery query;

        /*

        query.prepare("INSERT INTO student  VALUES (?, ?, ?, ?)");

        QVariantList IDs;

        IDs << 1 << 2 << 3 << 4;

        query.addBindValue(IDs);

        QVariantList names;

        names << "Tom" << "Jack" << "Jane" << "Jerry";

        query.addBindValue(names);

        QVariantList dept_names;

Dept_names <"computer" <"art" <"Mathematics" <"Foreign Language ";

        query.addBindValue(dept_names);

        QVariantList tot_creds;

        tot_creds << "10" << "11" << "12" << "13";

        query.addBindValue(tot_creds);

        if (!query.execBatch())

        {

            QMessageBox::critical(0, QObject::tr("Database Error"),

                                  query.lastError().text());

        }

        query.finish();

        */

        query.prepare("INSERT INTO tempTest (name, description) "

                      "VALUES (:name, :description)");

Query. bindValue (": name", "test ");

Query. bindValue (": description", "test data insertion ");

        query.exec();

        QString sql="SELECT name, description FROM tempTest";

        query.exec(sql);

        while (query.next())

        {

            QString name = query.value(0).toString();

            QString description = query.value(1).toString();

            qDebug() << name << ": " << description;

        }

    }

    else

    {

        return 1;

    }

    return a.exec();

}