文章目录[隐藏]

题目描述：

(1)模拟登陆界面，判别用户名和密码，给出合适的提示，如果超过三次，锁定输入。用代替密码；或者最新输入显示，前面的变成；安全性措施。
(2)同时添加如下图的加强验证（京东）。
(3)在触动滚动条时再出现空缺位置。
在这里插入图片描述
拓展：

增加注册页面，可供用户注册新用户
增加数字验证码区别人机

解题思路/算法分析/问题及解决

滑块验证就是将滑块的移动和图片小块的移动相绑定，在滑块松开时触发相对应的检查函数，为了有一定的容错率，设定滑块的位置与设定的位置相差3个像素以内即算验证成功。

每次的位置随机生成，同时随即从14张事先准备好的图片中选取一张作为背景图。
图片小块和背景图片分别放在两个不同的QLabel容器中。
每次刷新时将背景图片的相应位置抠出放于图片小块中，并将背景图片的相应部分置为白色以示区别。
拓展：
新增注册页部分就是点击按钮弹出注册页的对话框，可在里面输入新用户信息并保存到用户信息字典中，随后可用新注册的用户登录。
数字验证码由4位数字0-9和字母a-z及A-Z组成，随机在可行字符集中选取4个字符组成四位验证码，然后自动生成验证码以图片的方式呈现给用户。

实验代码

登录主界面：
登录验证：

def check_login_func(self):
        if not self.validate_line.text():
            QMessageBox.warning(self, "警告", "还未输入验证码")
            return
        validate_slide = Validate_page()
        r = validate_slide.exec_()
        if not r:
            return
        if self.validate.upper() == self.validate_line.text().upper():
            if USER_PWD.get(self.user_line.text()) == self.pwd_line.text():
                QMessageBox.information(self, 'Information', 'Log in Successfully!')
                self.nums = 0
                self.refresh()
                # self.close()
                # self.STU.exec()
            else:
                QMessageBox.critical(self, 'Wrong', 'Wrong Username or Password!')
                self.nums = self.nums + 1
                if self.nums == 3:
                    QMessageBox.critical(self, "wrong", "密码输错次数已达三次！")
                    self.close()

            self.user_line.clear()
            self.pwd_line.clear()
            self.validate_line.clear()
        else:
            QMessageBox.critical(self, "wrong", "验证码输入有误！")
            self.refresh()
            self.validate_line.clear()

自动生成验证码图片：

def get_chars():
        """生成给定长度的字符串，返回列表格式"""

        return random.sample(chars, length)

    def create_lines():
        """绘制干扰线"""

        line_num = random.randint(*n_line)  # 干扰线条数

        for i in range(line_num):
            # 起始点
            begin = (random.randint(0, size[0]), random.randint(0, size[1]))
            # 结束点
            end = (random.randint(0, size[0]), random.randint(0, size[1]))
            draw.line([begin, end], fill=(0, 0, 0))

    def create_points():
        """绘制干扰点"""

        chance = min(100, max(0, int(point_chance)))  # 大小限制在[0, 100]

        for w in range(width):
            for h in range(height):
                tmp = random.randint(0, 100)
                if tmp > 100 - chance:
                    draw.point((w, h), fill=(0, 0, 0))

    def create_strs():
        """绘制验证码字符"""

        c_chars = get_chars()
        strs = ' %s ' % ' '.join(c_chars)  # 每个字符前后以空格隔开

        font = ImageFont.truetype(font_type, font_size)
        font_width, font_height = font.getsize(strs)

        draw.text(((width - font_width) / 3, (height - font_height) / 3),
                  strs, font=font, fill=fg_color)

        return ''.join(c_chars)

    if draw_lines:
        create_lines()
    if draw_points:
        create_points()
    strs = create_strs()

    # 图形扭曲参数
    params = [1 - float(random.randint(1, 2)) / 100,
              0,
              0,
              0,
              1 - float(random.randint(1, 10)) / 100,
              float(random.randint(1, 2)) / 500,
              0.001,
              float(random.randint(1, 2)) / 500
              ]
    img = img.transform(size, Image.PERSPECTIVE, params)  # 创建扭曲

    img = img.filter(ImageFilter.EDGE_ENHANCE_MORE)  # 滤镜，边界加强（阈值更大）

    mstream = io.BytesIO()
    img.save(mstream, img_type)

    if save_img:
        img.save("validate.jpg", img_type)

    return mstream, strs

注册界面部分：
页面初始化：

def __init__(self):
        super(SigninPage, self).__init__()
        self.signin_user_label = QLabel('Username:', self)
        self.signin_pwd_label = QLabel('Password:', self)
        self.signin_pwd2_label = QLabel('Password:', self)
        self.signin_user_line = QLineEdit(self)
        self.signin_pwd_line = QLineEdit(self)
        self.signin_pwd2_line = QLineEdit(self)
        self.signin_button = QPushButton('Sign in', self)

        self.user_h_layout = QHBoxLayout()
        self.pwd_h_layout = QHBoxLayout()
        self.pwd2_h_layout = QHBoxLayout()
        self.all_v_layout = QVBoxLayout()

        self.lineedit_init()
        self.pushbutton_init()
        self.layout_init()

    def layout_init(self):
        self.user_h_layout.addWidget(self.signin_user_label)
        self.user_h_layout.addWidget(self.signin_user_line)
        self.pwd_h_layout.addWidget(self.signin_pwd_label)
        self.pwd_h_layout.addWidget(self.signin_pwd_line)
        self.pwd2_h_layout.addWidget(self.signin_pwd2_label)
        self.pwd2_h_layout.addWidget(self.signin_pwd2_line)

        self.all_v_layout.addLayout(self.user_h_layout)
        self.all_v_layout.addLayout(self.pwd_h_layout)
        self.all_v_layout.addLayout(self.pwd2_h_layout)
        self.all_v_layout.addWidget(self.signin_button)

        self.setLayout(self.all_v_layout)

    def lineedit_init(self):
        self.signin_user_line.setPlaceholderText("username")
        self.signin_pwd_line.setPlaceholderText("password")
        self.signin_pwd2_line.setPlaceholderText("password again")

        self.signin_pwd_line.setEchoMode(QLineEdit.Password)
        self.signin_pwd2_line.setEchoMode(QLineEdit.Password)

        self.signin_user_line.textChanged.connect(self.check_input_func)
        self.signin_pwd_line.textChanged.connect(self.check_input_func)
        self.signin_pwd2_line.textChanged.connect(self.check_input_func)

注册检验部分：

def check_signin_func(self):
        if self.signin_pwd_line.text() != self.signin_pwd2_line.text():
            QMessageBox.critical(self, 'Wrong', 'Two Passwords Typed Are Not Same!')
        elif self.signin_user_line.text() not in USER_PWD:
            USER_PWD[self.signin_user_line.text()] = self.signin_pwd_line.text()
            QMessageBox.information(self, 'Information', 'Register Successfully')
            self.close()
        else:
            QMessageBox.critical(self, 'Wrong', 'This Username Has Been Registered!')

        self.signin_user_line.clear()
        self.signin_pwd_line.clear()
        self.signin_pwd2_line.clear()

滑块验证部分：

class Validate_page(QDialog):
    def __init__(self):
        super(Validate_page, self).__init__()
        self.resize(600, 500)
        self.setWindowTitle("拖动滑块验证")
        self.initUI()
        self.Widget_init()
        self.refresh()
        # self.show()

    def initUI(self):
        # 初始化相关控件位置
        self.lb_bg = QLabel(self)
        self.lb_sl = QLabel(self)

        self.lb_bg.setStyleSheet("border: 2px solid red")
        # self.lb_sl.setStyleSheet("border: 2px solid blue")
        self.lb_bg.setGeometry(100, 100, 400, 200)

        self.lb_wz = QLabel(self)
        # self.lb_wz.setStyleSheet("border: 2px solid green")

        self.refresh()

        self.button = QPushButton("取消", self)
        self.button.setGeometry(400, 430, 100, 50)

        self.slider = QSlider(Qt.Horizontal, self)
        self.slider.setGeometry(100, 350, 400, 50)

    def Widget_init(self):
        # 初始化相关组件的信号连接
        self.slider.setMinimum(0)
        self.slider.setMaximum(360)
        self.slider.valueChanged.connect(self.slide)
        self.slider.sliderReleased.connect(self.check)
        self.button.clicked.connect(self.cancel)

    def slide(self, value):
        self.lb_sl.move(100 + value, self.answer_y)  # 将滑块与图片小块绑定
        # print(value)

    def refresh(self):
        import random
        # 随机生成验证区域
        self.answer_x = random.randint(100, 460)
        self.answer_y = random.randint(100, 260)
        pic = random.randint(0, 14)

        self.lb_sl.setGeometry(100, self.answer_y, 40, 40)
        self.lb_wz.setGeometry(self.answer_x, self.answer_y, 40, 40)
        img = cv2.imread(f"pic/{pic}.jpeg")  # 读取背景图片
        img = cv2.resize(img, (400, 200))
        x = self.answer_x - 100
        y = self.answer_y - 100
        img1 = copy.copy(img[y:y + 40, x:x + 40])  # 扣40*40的图片小块
        img[y:y + 40, x:x + 40] = 255  # 将被扣区域置为白色
        img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
        img1 = cv2.cvtColor(img1, cv2.COLOR_BGR2RGB)

        qt_img = QImage(img.data, 400, 200, QImage.Format_RGB888)
        qt_img1 = QImage(img1.data, 40, 40, QImage.Format_RGB888)
        self.lb_bg.setPixmap(QPixmap.fromImage(qt_img))
        self.lb_sl.setPixmap(QPixmap.fromImage(qt_img1))

    def check(self):  # 检验滑动验证是否成功
        # 获取设定区域坐标
        x = self.lb_sl.pos().x()
        y = self.lb_sl.pos().y()
        print(f"({x},{y})")
        if abs(x - self.answer_x) <= 3:  # 容错为3px
            QMessageBox.information(self, "恭喜", "验证成功")
            self.done(1)
        else:
            QMessageBox.critical(self, "错误", "验证失败")
            self.slider.setValue(0)
            self.refresh()

    def cancel(self):
        self.done(0)  # 点击取消滑动验证