1> 将网络聊天室重新实现一遍
服务器端
#include "widget.h"
#include "ui_widget.h"
Widget::Widget(QWidget *parent)
: QWidget(parent)
, ui(new Ui::Widget)
{
ui->setupUi(this);
ser = new QTcpServer(this);
}
Widget::~Widget()
{
delete ui;
}
void Widget::on_startBtn_clicked()
{
if(ui->startBtn->text() == "启动")
{
quint16 port = ui->lineEdit->text().toUInt();
if(ser->listen(QHostAddress::Any,port)==true)
{
QMessageBox::information(this,"成功","服务器启动成功");
}
else
{
QMessageBox::information(this,"失败","服务器启动失败");
}
//当启动服务器后,如果有客户端发来连接请求,那么该服务器端就会自动化发送一个newConnection信号
//我们可以将信号,连接到对应的槽函数
connect(ser,&QTcpServer::newConnection,this,&Widget::newconnection_slot);
ui->startBtn->setText("关闭");
}
else
{
ser->close();
ui->startBtn->setText("启动");
}
}
//关于readyread信号对应的槽函数的定义
void Widget::readyread_slots()
{
//判断客户端容器中,是否已经有退出的客户端,或者无效的客户端,或者无效的客户端,如果有,将其进行移除
for(int i=0;i<cliList.length();i++)
{
if(cliList[i]->state() == QTcpSocket::UnconnectedState)
{
//功能:判断当前套接字的状态
//参数:无
//返回值:readyread_slots表示无效的客服端
cliList.removeAt(i);
}
}
for(int i=0;i<cliList.length();i++)
{
if(cliList[i]->bytesAvailable()!=0)
{
//获取当前套接字中套接字中的待读数据的个数
//参数:无
//返回值:返回套接字中待读
//如果不等于0;表示有数据可读,可以使用readall读取数据
QByteArray msg = cliList[i]->readAll();
ui->msgWidget->addItem(QString::fromLocal8Bit(msg));
for(int j=0;j<cliList.length();j++)
{
if(i!=j)
{
cliList[j]->write(msg);
}
}
}
}
}
void Widget::newconnection_slot()
{
qDebug() << "有客户端发来连接请求";
QTcpSocket *socket = ser->nextPendingConnection();
cliList.append(socket);
//当有客户端向服务器发来数据时候,当前客户端套接字就会自动发送一个readyread信号
//我们就可以
connect(socket,&QTcpSocket::readyRead,this,&Widget::readyread_slots);
}
客户端
#include "widget.h"
#include "ui_widget.h"
Widget::Widget(QWidget *parent)
: QWidget(parent)
, ui(new Ui::Widget)
{
ui->setupUi(this);
this->resize(800,600);
this->setFixedSize(800,600);
this->setWindowTitle("网络聊天室");
list = new QListWidget(this);
list->resize(800,400);
edtsend = new QLineEdit(this);
edtsend->setPlaceholderText("发送消息");
edtsend->resize(450,80);
edtsend->move(50,420);
edtname = new QLineEdit(this);
edtname->setPlaceholderText("用户名");
edtname->resize(100,50);
edtname->move(50,500);
edtip = new QLineEdit(this);
edtip->setPlaceholderText("ip");
edtip->resize(300,50);
edtip->move(150,500);
edtport = new QLineEdit(this);
edtport->setPlaceholderText("port");
edtport->resize(300,50);
edtport->move(100,550);
btnsend = new QPushButton("发送",this);
btnsend->resize(100,50);
btnsend->move(600,450);
btnlink = new QPushButton("连接服务器",this);
btnlink->resize(100,50);
btnlink->move(600,550);
cli = new QTcpSocket(this);
connect(cli,&QTcpSocket::connected,this,&Widget::connected_slot);
connect(cli,&QTcpSocket::readyRead,this,&Widget::readyread_slot);
connect(cli,&QTcpSocket::disconnected,this,&Widget::disconnectes_slot);
connect(btnlink,&QPushButton::clicked,this,&Widget::on_connectBtn_clicked);
connect(btnsend,&QPushButton::clicked,this,&Widget::on_sendBtn_clicked);
// connect(btn,&QPushButton::clicked,this,&Widget::cliked_slot);
}
Widget::~Widget()
{
delete ui;
}
void Widget::connected_slot()
{
QMessageBox::information(this,"连接","连接服务器成功");
}
void Widget::readyread_slot()
{
QByteArray msg = cli->readAll();
list->addItem(QString::fromLocal8Bit(msg));
}
void Widget::disconnectes_slot()
{
QMessageBox::information(this, "断开", "断开服务器成功");
}
//信息发送按钮对应的槽函数
void Widget::on_sendBtn_clicked()
{
//1、将ui界面上的文本信息获取下来
QString msg = userName + ":" + edtsend->text();
//2、将该消息发送给服务器
cli->write(msg.toLocal8Bit());
//3、清空航编辑器中的内容
edtsend->clear();
//将消息放入ui界面中
QListWidgetItem *item = new QListWidgetItem(msg);
item->setTextAlignment(Qt::AlignRight);
list->addItem(item);
}
//连接服务器按钮对应的槽函数
void Widget::on_connectBtn_clicked()
{
if(btnlink->text() == "连接服务器")
{
userName = edtname->text(); //用户名
QString ip = edtip->text(); //ip地址
quint16 port = edtport->text().toUInt(); //端口号
cli->connectToHost(ip, port);
btnlink->setText("断开服务器");
}else
{
QString msg = userName + ": 离开聊天室";
cli->write(msg.toLocal8Bit());
cli->disconnectFromHost();
btnlink->setText("连接服务器");
}
}
2> 将数据库管理系统,进行完善
#include "widget.h"
#include "ui_widget.h"
Widget::Widget(QWidget *parent)
: QWidget(parent)
, ui(new Ui::Widget)
{
ui->setupUi(this);
//判断当前数据库操作对象中,是否包含了要处理的数据库
if(!db.contains("mydb.db"))
{
//添加一个数据库到当前数据库对象中
db = QSqlDatabase::addDatabase("QSQLITE");
//给数据库设置名字
db.setDatabaseName("mydb.db");
}
//此时,已经创建了一个数据库,但是没有打开
if(!db.open())
{
QMessageBox::information(this,"失败","数据库打开失败");
return;
}
//程序执行至此,数据库打开成功
//准备sql语句
QString sql = "create table if not exists Stu(numb int , name char , sex char , score double)";
//实例化一个sql语句的的执行者
QSqlQuery query;
if(!query.exec(sql))
{
QMessageBox::information(this,"提示","创建数据表失败");
return;
}
}
Widget::~Widget()
{
delete ui;
}
//添加学院信息按钮对应的槽函数
void Widget::on_pushButton_clicked()
{
//将ui界面上的相关信息获取下来
int ui_numb = ui->lineEdit->text().toUInt();
QString ui_name = ui->lineEdit_2->text();
QString ui_sex = ui->lineEdit_3->text();
double ui_score = ui->lineEdit_4->text().toDouble();
if(ui_sex==NULL || ui_numb==0 || ui_score==0 || ui_name==NULL)
{
QMessageBox::information(this,"提示","请将信息填写完整");
return;
}
//准备sql语句
QString sql = QString("insert into Stu values(%1,'%2','%3',%4)").arg(ui_numb).arg(ui_name).arg(ui_sex).arg(ui_score);
//执行sql语句
QSqlQuery query;
if(!query.exec(sql))
{
QMessageBox::information(this,"提示","添加数据表失败");
return;
}
else
{
QMessageBox::information(this,"提示","添加数据表成功");
}
}
//删除按钮对应的槽函数
void Widget::on_pushButton_2_clicked()
{
QString sql;
if(ui->lineEdit_2->text() == NULL)
{
sql = "delete * from Stu";
}
else
{
sql = QString("delete from Stu where name='%1'").arg(ui->lineEdit_2->text());
}
//执行sql语句
QSqlQuery query;
if(!query.exec(sql))
{
QMessageBox::information(this,"提示","删除数据表失败");
return;
}
else
{
QMessageBox::information(this,"提示","删除数据表成功");
}
}
//修改
void Widget::on_pushButton_3_clicked()
{
QString sql;
if(ui->lineEdit_2->text() == NULL)
{
sql = "delete * from Stu";
}
else
{
sql = QString("update stu set name='%1' from Stu where numb='%2'").arg(ui->lineEdit_2->text()).arg(ui->lineEdit->text());
}
//执行sql语句
QSqlQuery query;
if(!query.exec(sql))
{
QMessageBox::information(this,"提示","更新数据表失败");
return;
}
else
{
QMessageBox::information(this,"提示","更新数据表成功");
}
}
//查找按钮对应的槽函数
void Widget::on_pushButton_4_clicked()
{
QString sql;
if(ui->lineEdit_2->text() == NULL)
{
sql = "select * from Stu";
}
else
{
sql = QString("select * from Stu where name='%1'").arg(ui->lineEdit_2->text());
}
//执行sql语句
QSqlQuery query;
if(!query.exec(sql))
{
QMessageBox::information(this,"提示","查询数据表失败");
return;
}
else
{
QMessageBox::information(this,"提示","查询数据表成功");
}
//将查询结果展示到ui上
int i = 0;
while(query.next())
{
//这里面是任意一个查询的结果。query对象中保存的是当前的一个记录
//可以通过成员函数record
qDebug() << query.record().value(1).toString(); //每一次转变成字符串的值
//通过条用Qsqlrecord类的成员函数:value
for(int j=0;j<query.record().count();j++)
{
//qDebug() << query.record().value(j).toString();
QTableWidgetItem *item = new QTableWidgetItem(query.record().value(j).toString());
item->setTextAlignment(Qt::AlignCenter);
//将数据库中的数据依次存放到ui界面中
ui->tableWidget->setItem(i,j,item);
}
i++;
}
}