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。
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
运行结果
全部背景图片：
注册界面：
