01.15

 数据库改查

//删除按钮对应的槽函数处理
void Widget::on_delBtn_clicked()
{

    int numb=ui->numbEdit->text().toUInt();
    if(numb==0)
    {
        QMessageBox::information(this,"","请输入要删除的学号");
        return;
    }
    //准备sql语句
    QSqlQuery query;
    QString sql=QString("delete from stu_info_table where numb=%1").arg(numb);
    //执行sql语句
    if(!query.exec(sql))
    {
        QMessageBox::information(this,"","删除失败");
        return;
    }else {
        QMessageBox::information(this,"","删除成功");
    }
    ui->tableWidget->clearContents();
    on_showBtn_clicked();
}
//修改按钮对应的槽函数处理
void Widget::on_resBtn_clicked()
{
    int numb=ui->numbEdit->text().toUInt();
    QString name=ui->nameEdit->text();
    QString sex=ui->sexEdit->text();
    int score=ui->scoreEdit->text().toUInt();
    QSqlQuery query;
    if(!name.isEmpty())
    {
            QString sql=QString("update stu_info_table set name='%1' where numb=%2").arg(name).arg(numb);
            query.exec(sql);
    }
    if(!sex.isEmpty())
    {
            QString sql=QString("update stu_info_table set sex='%1' where numb=%2").arg(sex).arg(numb);
            query.exec(sql);
    }
    if(score!=0)
    {
            QString sql=QString("update stu_info_table set score=%1 where numb=%2").arg(score).arg(numb);
            query.exec(sql);
    }
     on_showBtn_clicked();
}

 视频灰度和均衡化

#include "widget.h"
#include 

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();
    //将本地的视频加载到程序中
    VideoCapture v;
    v.open("D:\\opencv\\heads\\01.mp4");
    //定义一个存放从视频里读取到一帧图像
    Mat src;
    Mat gray;
    Mat dst;
    while(v.read(src))
    {
        //显示图像
        imshow("test1",src);
        if(waitKey(30)==27)
        {
            break;
        }

    }
    while(v.read(src))
    {
        //显示图像
        cvtColor(src,gray,CV_BGR2GRAY);
        imshow("test2",gray);
        if(waitKey(30)==27)
        {
            break;
        }
    }
    while(v.read(src))
    {
        //显示图像
        cvtColor(src,gray,CV_BGR2GRAY);
        equalizeHist(gray,dst);
        imshow("test3",dst);
        if(waitKey(30)==27)
        {
            break;
        }
    }
    return a.exec();
}