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C++ 从QVariantList获取字符串_C++_Qt - Fatal编程技术网

C++ 从QVariantList获取字符串

C++ 从QVariantList获取字符串,c++,qt,C++,Qt,数据库中的数据位于QVariantList中,我想循环遍历它并获得firstname QVariantList sqlData = database->loadDatabase("quotes.db", "quotes"); for (int i = 1; i <= sqlData.size(); i++) { qDebug() << sqlData.value(i); } 如何调试“firstname”的值?格伦福德 感谢QVarian

数据库中的数据位于QVariantList中,我想循环遍历它并获得firstname

QVariantList sqlData = database->loadDatabase("quotes.db", "quotes");
for (int i = 1; i <= sqlData.size(); i++)
    {
        qDebug() << sqlData.value(i);
    }
如何调试“firstname”的值?格伦福德


感谢

QVariant list是一个QVariant列表,对象有一个特定的迭代器

QVariantList sqlData = database->loadDatabase("quotes.db", "quotes");
for (QVariantList::iterator j = sqlData.begin(); j != sqlData.end(); j++)
{
    qDebug() << "iterating through QVariantList ";
    qDebug() << (*j).toString(); // Print QVariant
}
qvariantlistsqldata=database->loadDatabase(“quotes.db”、“quotes”);
对于(QVariantList::迭代器j=sqlData.begin();j!=sqlData.end();j++)
{

qDebug()试试看没什么帮助,我怎么能把名字作为目标呢?看看Qt文档,我觉得
sqlData.value(I.toMap().value(“firstname”);
可能适合你。这就产生了:QVariant(QString,“Glenford”)你知道如何输出Glenford吗?在
QVariant(QString,“Glenford”)上试试
value
请查看文档,了解类似这样相对简单的问题。
QVariantList sqlData = database->loadDatabase("quotes.db", "quotes");
for (QVariantList::iterator j = sqlData.begin(); j != sqlData.end(); j++)
{
    qDebug() << "iterating through QVariantList ";
    qDebug() << (*j).toString(); // Print QVariant
}