实验

QTime和字符串相互转换

QDate和字符串相互转换

QDateTime和字符串相互转换

QCalendarWidget使用

year，month，day，minute，second，msec，dayOfWeek, dayto方法/属性的使用

布局

datetimeexample.cpp

#include "datetimeexample.h"
#include "ui_datetimeexample.h"
#include <QMessageBox>

dateTimeExample::dateTimeExample(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::dateTimeExample)
{
    ui->setupUi(this);
}

dateTimeExample::~dateTimeExample()
{
    delete ui;
}

void dateTimeExample::on_btnReadNow_clicked()
{
    QDateTime curDateTime =QDateTime::currentDateTime();//读取到当前的日期时间
    ui->timeEdit->setTime(curDateTime.time());  //取time()
    ui->editTime->setText(curDateTime.toString("HH:mm:ss"));

    ui->dateEdit->setDate(curDateTime.date());  //取date()
    ui->editDate->setText(curDateTime.toString("yyyy-MM-dd"));

    ui->dateTimeEdit->setDateTime(curDateTime);
    ui->editDateTime->setText(curDateTime.toString("yyyy-MM-dd HH:mm:ss"));
}


void dateTimeExample::on_btnSetTime_clicked()
{
    QString str = ui->editTime->text();
    str= str.trimmed();
    if(!str.isEmpty())
    {
        QTime tm = QTime::fromString(str,"HH:mm:ss");
        ui->timeEdit->setTime(tm);
    }
}


void dateTimeExample::on_btnSetDate_clicked()
{
    QString str = ui->editDate->text();
    str= str.trimmed();
    if(!str.isEmpty())
    {
        QDate dt = QDate::fromString(str,"yyyy-MM-dd");
        ui->dateEdit->setDate(dt);
    }
}



void dateTimeExample::on_btnSetDateTime_clicked()
{
    QString str = ui->editDateTime->text();
    str= str.trimmed();
    if(!str.isEmpty())
    {
        QDateTime datetime = QDateTime::fromString(str,"yyyy-MM-dd HH:mm:ss");
        ui->dateTimeEdit->setDateTime(datetime);
    }
}


void dateTimeExample::on_btnShowDateTime_clicked()
{
    QDateTime curDateTime = QDateTime::currentDateTime();
    QDate dt2;
    dt2.setDate(2025,01,01);
    QString temp = curDateTime.toString("yyyy-MM-dd HH:mm:ss zzz");
    QString str=QString("当前日期时间：%1").arg(temp);
    str+="\n";
    str+=QString("年：%1").arg(curDateTime.date().year());
    str+="\n";
    str+=QString("月：%1").arg(curDateTime.date().month());
    str+="\n";
    str+=QString("月：%1").arg(curDateTime.date().day());
    str+="\n";
    str+=QString("时：%1").arg(curDateTime.time().hour());
    str+="\n";
    str+=QString("分：%1").arg(curDateTime.time().minute());
    str+="\n";
    str+=QString("秒：%1").arg(curDateTime.time().second());
    str+="\n";
    str+=QString("毫秒：%1").arg(curDateTime.time().msec());
    str+="\n";
    str+="-----------------------------\n";
    str+=QString("星期：%1").arg(curDateTime.date().dayOfWeek());
    str+="\n";
    str+=QString("toLocal8Bit().data():%1").arg(temp.toLocal8Bit().data());
    str+="\n";
    str+=QString("距离%1还有:%2天").arg(dt2.toString("yyyy年MM月dd日")).arg(curDateTime.date().daysTo(dt2));

    QMessageBox::information(this,"信息",str);

}


void dateTimeExample::on_calendarWidget_selectionChanged()
{
    QDate date = ui->calendarWidget->selectedDate();
    ui->editCalendar->setText(date.toString("yyyy年MM月dd日"));
}

效果