怎么才算清掉所有相关的实例？- #include "dialog.h"
- #include <QApplication>
- #include <QSqlDatabase>
- #include <QtDebug>
- #include <QSqlError>
- int main(int argc, char *argv[])
- {
- QApplication a(argc, argv);
- QSqlDatabase db;
- db = QSqlDatabase::addDatabase("QMYSQL", "mysqlLocal");
- db.setHostName("127.0.0.1");
- db.setDatabaseName("express_plc");
- db.setUserName("remoteuser");
- db.setPassword("8ik,9ol");
- if (!db.open()) {
- qDebug() << "database open failure";
- qDebug() << db.lastError().text();
- } else {
- qDebug() << "database open successful";
- }
- if (!db.open()) {
- qDebug() << "database second open failure";
- qDebug() << db.lastError().text();
- } else {
- qDebug() << "database second open successful";
- }
- db.close();
- if (db.isValid())
- qDebug("vaild！");
- //db.removeDatabase("mysqlLocal");
- {
- QString name;
- name = QSqlDatabase::database("mysqlLocal").connectionName();
- QSqlDatabase::removeDatabase(name);
- }
- if (db.isValid())
- qDebug("still vaild！");
- return a.exec();
- }
输出：
database open successful
database second open successful
vaild！
QSqlDatabasePrivate::removeDatabase: connection 'mysqlLocal' is still in use, all queries will cease to work.
我上面的代码，db都没有用来查询，我也关闭了，可是还报，真的不知道，怎样才算
清掉所有相关的实例。---------------------------------------------------------------------------------------------------------------------------------------------------------
