【Qt聊天室客户端】登录窗口

1. 验证码

具体实现

登录界面中创建验证码图片空间，并添加到布局管理器中

主要功能概述（创建一个verifycodewidget类专门实现验证码操作）

详细代码

// 头文件

#ifndef VERIFYCODEWIDGET_H
#define VERIFYCODEWIDGET_H

#include <QWidget>
#include<QRandomGenerator>

class verifycodewidget : public QWidget
{
    Q_OBJECT
public:
    explicit verifycodewidget(QWidget *parent = nullptr);


    // 生成随机的验证码字符串
    QString generateVerifyCode();

    // 重新生成验证码并显示到界面上
    void refreshVerifyCode();

    // 检查输入的验证码是否与生成的验证码匹配
    bool checkVerifyCode(const QString& verifyCode);

    // 重写 paintEvent 以绘制验证码到界面上
    void paintEvent(QPaintEvent* event) override;

    // 重写 mousePressEvent，当用户点击时刷新验证码并重新显示
    void mousePressEvent(QMouseEvent* event) override;

private:
    // 用于生成随机数的随机数生成器
    QRandomGenerator randomGenerator;

    // 存储当前验证码的值
    QString verifyCode = "";


signals:

};

#endif // VERIFYCODEWIDGET_H

// 实现文件

#include "verifycodewidget.h"

#include<QPainter>

#include"model/data.h"

verifycodewidget::verifycodewidget(QWidget *parent)
    : QWidget(parent),randomGenerator(model::getTime())
{
    verifyCode = generateVerifyCode();
}

//随机生成验证码
QString verifycodewidget::generateVerifyCode()
{
    QString code;
    for(int i = 0;i<4;++i){
        int init = 'A';
        init += randomGenerator.generate()%26;
        code += static_cast<QChar>(init);
    }
    return code;
}

void verifycodewidget::refreshVerifyCode()
{
    verifyCode = generateVerifyCode();
    this->update();
}

bool verifycodewidget::checkVerifyCode(const QString &verifyCode)
{
    return this->verifyCode.compare(verifyCode, Qt::CaseInsensitive) == 0;
}

void verifycodewidget::paintEvent(QPaintEvent *event)
{
    (void) event;
    const int width = 180;
    const int height = 80;

    QPainter painter(this);
    QPen pen;
    QFont font("楷体",25,QFont::Bold,true);
    painter.setFont(font);

    // 画点: 添加随机噪点
    for(int i = 0; i < 100; i++)
    {
        pen = QPen(QColor(randomGenerator.generate() % 256, randomGenerator.generate() % 256, randomGenerator.generate() % 256));
        painter.setPen(pen);
        painter.drawPoint(randomGenerator.generate() % width, randomGenerator.generate() % height);
    }

    // 画线: 添加随机干扰线
    for(int i = 0; i < 5; i++)
    {
        pen = QPen(QColor(randomGenerator.generate() % 256, randomGenerator.generate() % 256, randomGenerator.generate() % 256));
        painter.setPen(pen);
        painter.drawLine(randomGenerator.generate() % width, randomGenerator.generate() % height,
                         randomGenerator.generate() % width, randomGenerator.generate() % height);
    }

    // 绘制验证码
    for(int i = 0; i < verifyCode.size(); i++)
    {
        pen = QPen(QColor(randomGenerator.generate() % 255, randomGenerator.generate() % 255, randomGenerator.generate() % 255));
        painter.setPen(pen);
        painter.drawText(5+20*i, randomGenerator.generate() % 10, 30, 30, Qt::AlignCenter, QString(verifyCode[i]));
    }
}

void verifycodewidget::mousePressEvent(QMouseEvent *event)
{
    (void) event;
    this->refreshVerifyCode();
}