1，主界面

2，代码

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include    <QTcpSocket>
#include    <QLabel>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT
private:
    QTcpSocket  *tcpClient;  //socket
    QLabel  *LabSocketState;  //状态栏显示标签

    QString getLocalIP();//获取本机IP地址
protected:
    void    closeEvent(QCloseEvent *event);
public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
//自定义槽函数
    void    onConnected();
    void    onDisconnected();
    void    onSocketStateChange(QAbstractSocket::SocketState socketState);
    void    onSocketReadyRead();//读取socket传入的数据
//
    void on_actConnect_triggered();

    void on_actDisconnect_triggered();

    void on_actClear_triggered();

    void on_btnSend_clicked();

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include    <QHostAddress>
#include    <QHostInfo>

QString MainWindow::getLocalIP()
{
    QString hostName=QHostInfo::localHostName();//本地主机名
    QHostInfo   hostInfo=QHostInfo::fromName(hostName);
    QString   localIP="";

    QList<QHostAddress> addList=hostInfo.addresses();//

    if (!addList.isEmpty())
    for (int i=0;i<addList.count();i++)
    {
        QHostAddress aHost=addList.at(i);
        if (QAbstractSocket::IPv4Protocol==aHost.protocol())
        {
            localIP=aHost.toString();
            break;
        }
    }
    return localIP;
}
void MainWindow::closeEvent(QCloseEvent *event)
{
    if (tcpClient->state()==QAbstractSocket::ConnectedState)
        tcpClient->disconnectFromHost();
    event->accept();
}

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

    tcpClient=new QTcpSocket(this); //创建socket变量

    LabSocketState=new QLabel(u8"Socket状态：");//状态栏标签
    LabSocketState->setMinimumWidth(250);
    ui->statusBar->addWidget(LabSocketState);

    QString localIP=getLocalIP();//本机IP
    this->setWindowTitle(this->windowTitle()+u8"----本机IP："+localIP);
    ui->comboServer->addItem(localIP);


    connect(tcpClient,SIGNAL(connected()),this,SLOT(onConnected()));
    connect(tcpClient,SIGNAL(disconnected()),this,SLOT(onDisconnected()));

    connect(tcpClient,SIGNAL(stateChanged(QAbstractSocket::SocketState)),
            this,SLOT(onSocketStateChange(QAbstractSocket::SocketState)));
    connect(tcpClient,SIGNAL(readyRead()),
            this,SLOT(onSocketReadyRead()));
}

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

void MainWindow::onConnected()
{ //connected()信号槽函数
    ui->plainTextEdit->appendPlainText(u8"**已连接到服务器");
    ui->plainTextEdit->appendPlainText(u8"**peer address:"+
                                   tcpClient->peerAddress().toString());
    ui->plainTextEdit->appendPlainText(u8"**peer port:"+
                                   QString::number(tcpClient->peerPort()));
    ui->actConnect->setEnabled(false);
    ui->actDisconnect->setEnabled(true);
}

void MainWindow::onDisconnected()
{//disConnected()信号槽函数
    ui->plainTextEdit->appendPlainText(u8"**已断开与服务器的连接");
    ui->actConnect->setEnabled(true);
    ui->actDisconnect->setEnabled(false);
}

void MainWindow::onSocketReadyRead()
{//readyRead()信号槽函数
    while(tcpClient->canReadLine())
        ui->plainTextEdit->appendPlainText("[in] "+tcpClient->readLine());
}

void MainWindow::onSocketStateChange(QAbstractSocket::SocketState socketState)
{//stateChange()信号槽函数
    switch(socketState)
    {
    case QAbstractSocket::UnconnectedState:
        LabSocketState->setText(u8"scoket状态：UnconnectedState");
        break;
    case QAbstractSocket::HostLookupState:
        LabSocketState->setText(u8"scoket状态：HostLookupState");
        break;
    case QAbstractSocket::ConnectingState:
        LabSocketState->setText(u8"scoket状态：ConnectingState");
        break;

    case QAbstractSocket::ConnectedState:
        LabSocketState->setText(u8"scoket状态：ConnectedState");
        break;

    case QAbstractSocket::BoundState:
        LabSocketState->setText(u8"scoket状态：BoundState");
        break;

    case QAbstractSocket::ClosingState:
        LabSocketState->setText(u8"scoket状态：ClosingState");
        break;

    case QAbstractSocket::ListeningState:
        LabSocketState->setText(u8"scoket状态：ListeningState");
    }
}

void MainWindow::on_actConnect_triggered()
{//连接到服务器
    QString     addr=ui->comboServer->currentText();
    quint16     port=ui->spinPort->value();
    tcpClient->connectToHost(addr,port);
//    tcpClient->connectToHost(QHostAddress::LocalHost,port);
}

void MainWindow::on_actDisconnect_triggered()
{//断开与服务器的连接
    if (tcpClient->state()==QAbstractSocket::ConnectedState)
        tcpClient->disconnectFromHost();
}

void MainWindow::on_actClear_triggered()
{
    ui->plainTextEdit->clear();
}

void MainWindow::on_btnSend_clicked()
{//发送数据
    QString  msg=ui->editMsg->text();
    ui->plainTextEdit->appendPlainText("[out] "+msg);
    ui->editMsg->clear();
    ui->editMsg->setFocus();

    QByteArray  str=msg.toUtf8();
    str.append('\n');
    tcpClient->write(str);
}