#if QT_CONFIG(regularexpression)
    template<typename T>
    inline QList<T> findChildren(const QRegularExpression &re, Qt::FindChildOptions options = Qt::FindChildrenRecursively) const
        typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
        QList<T> list;
        qt_qFindChildren_helper(this, re, ObjType::staticMetaObject,
                                reinterpret_cast<QList<void *> *>(&list), options);
        return list;
#endif // QT_CONFIG(regularexpression)

2、实现 释放(delete)QTableWidget中动态增加(new)的子控件

    qDeleteAll(ui->tableWidget->findChildren<MyComboBox *>());
    qDeleteAll(ui->tableWidget->findChildren<MyDoubleSpinBox *>());

MyComboBox、MyDoubleSpinBox分别是继承自QComboBox、QDoubleSpinBox的自定义类，当子控件为其他类型时，将MyComboBox 或MyDoubleSpinBox

修改为需要寻找的子控件的类型即可。