QT学习之路七（qt的数据库操作）

迷南。 2022-07-12 08:32 267阅读 0赞

上一篇博客说了，我在做银行管理系统，所以少不了数据的操作，刚开始的时候，我想用mysql做的，但是qtcreator自身并没有mysql的驱动，于是上网，找了好久，跟着网上的教程，把mysql编译了一下，我按着教程编译出来了，但是不知为什么，我的qtcreator还是没有识别mysql的驱动文件，为此，我将近花了两天的时间，qtcreate也被我卸了好几次，mysql的驱动也编译了好几次，但是，我尝尽了所有的办法，甚至将别人编译的文件也试着下载看看效果，很遗憾，还是没有用，无奈之下，我选择了sqlite3来做，我打算用qt把银行管理的系统做完后，再抽一点时间，用mfc和Windows下的网络编程实现一下，qt固然好用，但它已经把所有的东西都封装好了，我不能仅仅满足于qt提供的库，我还是要花点时间在Windows下的网络编程以及系统编程，Windows下的话mysql就能用了，哎，浪费了两天时间，最终还是没有装好，还是有点遗憾。

以下是我学qtsqlite3操作的一个例子，如果有需要的朋友可以看下：

/********************************************************************************
    ** Form generated from reading UI file 'sql.ui'
    **
    ** Created: Thu Feb 16 14:03:41 2017
    **      by: Qt User Interface Compiler version 4.8.1
    **
    ** WARNING! All changes made in this file will be lost when recompiling UI file!
    ********************************************************************************/
    
    #ifndef UI_SQL_H
    #define UI_SQL_H
    
    #include <QtCore/QVariant>
    #include <QtGui/QAction>
    #include <QtGui/QApplication>
    #include <QtGui/QButtonGroup>
    #include <QtGui/QHeaderView>
    #include <QtGui/QMainWindow>
    #include <QtGui/QMenuBar>
    #include <QtGui/QStatusBar>
    #include <QtGui/QToolBar>
    #include <QtGui/QWidget>
    
    QT_BEGIN_NAMESPACE
    
    class Ui_sql
    {
    public:
        QMenuBar *menuBar;
        QToolBar *mainToolBar;
        QWidget *centralWidget;
        QStatusBar *statusBar;
    
        void setupUi(QMainWindow *sql)
        {
            if (sql->objectName().isEmpty())
                sql->setObjectName(QString::fromUtf8("sql"));
            sql->resize(400, 300);
            menuBar = new QMenuBar(sql);
            menuBar->setObjectName(QString::fromUtf8("menuBar"));
            sql->setMenuBar(menuBar);
            mainToolBar = new QToolBar(sql);
            mainToolBar->setObjectName(QString::fromUtf8("mainToolBar"));
            sql->addToolBar(mainToolBar);
            centralWidget = new QWidget(sql);
            centralWidget->setObjectName(QString::fromUtf8("centralWidget"));
            sql->setCentralWidget(centralWidget);
            statusBar = new QStatusBar(sql);
            statusBar->setObjectName(QString::fromUtf8("statusBar"));
            sql->setStatusBar(statusBar);
    
            retranslateUi(sql);
    
            QMetaObject::connectSlotsByName(sql);
        } // setupUi
    
        void retranslateUi(QMainWindow *sql)
        {
            sql->setWindowTitle(QApplication::translate("sql", "sql", 0, QApplication::UnicodeUTF8));
        } // retranslateUi
    
    };
    
    namespace Ui {
        class sql: public Ui_sql {};
    } // namespace Ui
    
    QT_END_NAMESPACE
    
    #endif // UI_SQL_H

#ifndef CONNECTION_H
    #define CONNECTION_H
    
    #include <QMessageBox>
    #include <QSqlDatabase>
    #include <QSqlQuery>
    
    static bool createConnection()
    {
        QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
        db.setDatabaseName("use.db");
        if(!db.open())
        {
            QMessageBox::critical(0,"cannot open database","unable to establsh a database connection.",QMessageBox::Cancel);
            return false;
        }
        QSqlQuery query;
        query.exec("create table customers(customerId INTEGER PRIMARY KEY,name varchar(50),city varchar(50),"
                   "customerType varchar(50),addTime date,addFromDepartment  varchar(10),quantity INTEGER );");
        query.exec(QObject::tr("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('张志国','中国','普通客户','2011-10-22','财务部',3);"));
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('靳红浩','法国','主要客户','2012-11-1','销售部',2) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('高武明','中国','普通客户','2013-5-12','编辑部',12) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('王玲菲','德国','特殊客户','2007-1-12','编辑部',5) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('马达达','中国','主要客户','2008-2-19','财务部',3) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('马凯文','德国','特殊客户','2000-4-23','财务部',6) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('姚明明','美国','特殊客户','2011-5-23','编辑部',2) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('余铭宏','中国','主要客户','2012-12-2','销售部',7) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('张艺谋','法国','特殊客户','2013-1-2','编辑部',2) ;");
        query.exec("insert into customers(name,city,customerType,addTime,addFromDepartment,quantity) values('张斯五','中国','普通客户','2010-1-3','销售部',1);");
    
        query.exec("create table student(id INTEGER,name TEXT, primary key(id))");
        query.exec("insert into student values(1,'LiuTao');");
        query.exec("insert into student values(2,'WangHong');");
        query.exec("insert into student values(3,'WangHong');");
        query.exec("insert into student values(4,'WangHong');");
        query.exec("insert into student values(5,'WangHong');");
        query.exec("insert into student values(6,'WangHong');");
    
        query.exec("create table save_user(account TEXT, passward TEXT, name TEXT, moto TEXT, likes INTEGER, vip INTEGER, primary key(account))");
        query.exec("insert into save_user values('88888888','hujianfei','胡剑飞', '我想回家',8,1)");
        return true;
    }
    
    #endif // CONNECTION_H

#ifndef SQL_H
    #define SQL_H
    
    #include <QMainWindow>
    
    namespace Ui {
    class sql;
    }
    
    class sql : public QMainWindow
    {
        Q_OBJECT
        
    public:
        explicit sql(QWidget *parent = 0);
        ~sql();
        
    private:
        Ui::sql *ui;
    };
    
    #endif // SQL_H

#include "sql.h"
    #include "ui_sql.h"
    #include <QDebug>
    #include <QSqlQuery>
    #include <QSqlTableModel>
    #include <QSqlRelationalTableModel>
    #include <QTableView>
    #include <QMessageBox>
    #include <QSqlError>
    
    sql::sql(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::sql)
    {
        ui->setupUi(this);
    
        QSqlQueryModel *model = new QSqlQueryModel(this);
        model->setQuery("select * from student");
        model->setHeaderData(0,Qt::Horizontal, tr("学号"));
        model->setHeaderData(1,Qt::Horizontal, tr("姓名"));
    
        QTableView *view = new QTableView(this);
        view->setModel(model);
    
        setCentralWidget(view);
    
    }
    
    sql::~sql()
    {
        delete ui;
    }

#include <QtGui/QApplication>
    #include <QSqlDatabase>
    #include <QDebug>
    #include "connection.h"
    #include <QVariant>
    #include <QStringList>
    #include <QSqlQuery>
    #include <QSqlTableModel>
    #include <QSqlRelationalTableModel>
    #include <QTableView>
    #include <QMessageBox>
    #include <QSqlError>
    #include <QTextCodec>
    #include "sql.h"
    
    int main(int argc, char *argv[])
    {
        QApplication a(argc, argv);
    
        QTextCodec::setCodecForTr(QTextCodec::codecForLocale());           			 //将字体乱码变为中文
        //QTextCodec::setCodecForTr(QTextCodec::codecForName("gb18030"));     			//使用GB18030字符集 效果和上一样
        QTextCodec::setCodecForCStrings(QTextCodec::codecForLocale());      			//将之后用到的不是显示的中文字符不显示乱码
    
        if(!createConnection())
        {
            return 1;
        }
    
    //    QSqlQuery query;
    //    query.exec("select * from student");
    //    while(query.next())
    //    {
    //        qDebug()<<query.value(0).toInt()<<query.value(1).toString();
    //    }
    
        sql w;
        w.show();
        
        return a.exec();
    }