qt数据库登录系统

#include <QCoreApplication>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QSqlError>
#include <QDebug>

bool login(const QString &username, const QString &password) {
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
    db.setDatabaseName("users.db");

    if (!db.open()) {
        qDebug() << "Database error:" << db.lastError().text();
        return false;
    }

    QSqlQuery query;
    query.prepare("SELECT * FROM users WHERE username = :username AND password = :password");
    query.bindValue(":username", username);
    query.bindValue(":password", password);

    if (query.exec() && query.next()) {
        qDebug() << "Login successful!";
        return true;
    } else {
        qDebug() << "Login failed:" << query.lastError().text();
        return false;
    }
}

int main(int argc, char *argv[]) {
    QCoreApplication a(argc, argv);

    QString username = "admin";
    QString password = "password";

    if (login(username, password)) {
        // 登录成功后的操作
    } else {
        // 登录失败后的操作
    }

    return a.exec();
}