在 Pyside6 上失去焦点 QLineEdit 后进行验证

您徒劳地删除了这个问题，您在其中更详细地描述了您将要做什么并提供了一个代码示例。

所以 - 你没有回答为什么你决定使用小部件QLineEdit。
我建议您使用年龄字段的小部件QSpinBox。

将导入更改为您自己的（PySide6）并尝试。你不能输入任何东西18 <= age <= 80

import sys
'''
from PySide6.QtCore import (QCoreApplication, QDate, QDateTime, QLocale,
    QMetaObject, QObject, QPoint, QRect,
    QSize, QTime, QUrl, Qt)
from PySide6.QtGui import (QBrush, QColor, QConicalGradient, QCursor,
    QFont, QFontDatabase, QGradient, QIcon,
    QImage, QKeySequence, QLinearGradient, QPainter,
    QPalette, QPixmap, QRadialGradient, QTransform)
from PySide6.QtWidgets import (QApplication, QGridLayout, QHBoxLayout, QLabel,
    QLineEdit, QMainWindow, QSizePolicy, QWidget)
'''

from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.Qt import *

# ??? from test import *


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        if not MainWindow.objectName():
            MainWindow.setObjectName(u"MainWindow")
        MainWindow.resize(371, 118)
        self.centralwidget = QWidget(MainWindow)
        self.centralwidget.setObjectName(u"centralwidget")
        
        self.gridLayout = QGridLayout(self.centralwidget)
        self.gridLayout.setObjectName(u"gridLayout")
        
        self.label = QLabel(self.centralwidget)
        self.label.setObjectName(u"label")

#        self.lineEdit = QLineEdit(self.centralwidget)
        self.spinBox = QSpinBox(self.centralwidget)                    # !!! + 

        self.label_2 = QLabel(self.centralwidget)
        self.label_2.setObjectName(u"label_2")

        self.lineEdit_2 = QLineEdit(self.centralwidget)
        self.lineEdit_2.setObjectName(u"lineEdit_2")

        self.gridLayout.addWidget(self.label, 0, 0)
        self.gridLayout.addWidget(self.spinBox, 0, 1)                  # !!! +
        self.gridLayout.addWidget(self.label_2, 1, 0)
        self.gridLayout.addWidget(self.lineEdit_2, 1, 1)

        MainWindow.setCentralWidget(self.centralwidget)
        self.retranslateUi(MainWindow)
        QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(QCoreApplication.translate("MainWindow", u"MainWindow", None))
        self.label.setText(QCoreApplication.translate("MainWindow", u"\u0412\u043e\u0437\u0440\u0430\u0441\u0442", None))
        self.label_2.setText(QCoreApplication.translate("MainWindow", u"\u0427\u0442\u043e-\u0442\u043e \u0434\u0440\u0443\u0433\u043e\u0435", None))
    

class Test(QMainWindow, Ui_MainWindow):
    def __init__(self):
        super(Test, self).__init__()
        self.setupUi(self)
        
        self.spinBox.setRange(18, 80)                                  # !!! +
        

if __name__ == "__main__":
    app = QApplication(sys.argv)
    app.setFont(QtGui.QFont("Times", 12, QtGui.QFont.Bold))
    window = Test()
    window.show()
    sys.exit(app.exec())