QVariant

QVariant:可以接收int,double,QDatetime,QPoint,QMap,QList...多种数据类型，便是和boost:variant不太一样，它并不是一个模板类，一次只能接收一个数据

#include<QVariant>
#include<iostream>
#include<QDateTime>
#include<QPoint>
using namespace std;

int main()
{
    QVariant v = 10;
    int i = v.toInt();
    cout << i << endl;
    v = "abc";
    cout << v.toString().toStdString() << endl;
    v.setValue(20);
    cout << v.toDouble() << endl;
    cout << v.canConvert<int>()<<endl;
    QDateTime dt;
    cout << v.canConvert<QDateTime>()<<endl;//0
    cout << dt.currentDateTime().toLocalTime().toString("yyyy.MM.dd").toStdString()<<endl;
    v.setValue(dt);//equals to v = dt;
    if(v.type()==QVariant::DateTime){
        cout << v.toDateTime().currentDateTime().toLocalTime().toString("yyyy.MM.dd").toStdString() << endl;
    }
    cout << v.canConvert<QDateTime>()<<endl;//1
}



10
abc
20
1
0
2011.07.02
2011.07.02
1