qt链接sqlite轻型数据库

Posted 2022-12-12 长安紫薯

#include "studentdialog.h"
#include "ui_studentdialog.h"

StudentDialog::StudentDialog(QWidget *parent)
    : QDialog(parent)
    , ui(new Ui::StudentDialog)

    ui->setupUi(this);

    //程序启动时创建
    createDB();
    createTable();
    queryTable();


StudentDialog::~StudentDialog()

    delete ui;


void StudentDialog::createDB()
    //数据库驱动，默认在本机，链接地址用户名密码均可省略
    db = QSqlDatabase::addDatabase("QSQLITE");
    //没有会自动创建，已有会直接打开
    db.setDatabaseName("stu.db");
    if(db.open())
        qDebug() << "创建/打开数据库成功!";
    else
        qDebug() << "创建/打开数据库失败!";
    

void StudentDialog::createTable()
    QSqlQuery query;
    QString str = QString("create table tb_student ("
                          "id int primary key not null,"
                          "name text not null,"
                          "score real not null)");
    if(query.exec(str) == false)
        qDebug() << str;
    else
        qDebug() << "创建表成功!"; //第一次创建，之后不会再创建
    


void StudentDialog::queryTable()
    QString str = QString("select * from tb_student");
    model.setQuery(str);
    ui->tableView->setModel(&model);  //参数要地址





void StudentDialog::on_insertButton_clicked()

    //从页面获取用户填写内容
    QSqlQuery query;
    int id = ui->idEdit->text().toInt();
    QString name = ui->nameEdit->text();
    double score = ui->scoreEdit->text().toDouble();

    //占位符方式
    QString str = QString("insert into tb_student values(%1,'%2',%3)")
            .arg(id).arg(name).arg(score);
    if(query.exec(str)==false)
        qDebug() << str;
    else
        qDebug() << "插入记录成功!";
        queryTable();
    



void StudentDialog::on_deleteButton_clicked()

    QSqlQuery query;
    int id = ui->idEdit->text().toInt();
    QString str = QString("delete from tb_student where id = %1").arg(id);
    if(query.exec(str)==false)
        qDebug() << str;
    else
        qDebug() << "删除记录成功!";
        queryTable();
    



void StudentDialog::on_updateButton_clicked()

    QSqlQuery query;
    int id = ui->idEdit->text().toInt();
    QString name = ui->nameEdit->text();
    double score = ui->scoreEdit->text().toDouble();

    QString str = QString("update tb_student set name= '%1',score= %2 where id = %3")
            .arg(name).arg(score).arg(id);
    if(query.exec(str)==false)
        qDebug() << str;
    else
        qDebug() << "修改记录成功!";
        queryTable();
    



void StudentDialog::on_clearButton_clicked()

    ui->idEdit->setText("");
    ui->nameEdit->setText("");
    ui->scoreEdit->setText("");