[PyQt] manage display date

[atlass218]

I am trying to create a desktop application with QtDesigner and pyqt5.
I created a Groupbox with QtDesigner in which I put 03 lineEdit, successively for the day, month and year, a button to activate a function and a linedit with readonly option to display the complete introduced date.
Here are some pictures that reflect the result of my code: the first 03 pictures show a correct date but the 4th picture shows an incorrect date (the day is past 31 and the month is past 12)

correct display:







incorrect display :



code python :

  def insert_date(self) :

           
            if (10<= int(self.lineEdit_day.text())<= 31 ) or (len(self.lineEdit_day.text())>1) :
                day_of_date=self.lineEdit_day.text()
            elif  (1<=int(self.lineEdit_day.text())<=9 ) :
                day_of_date='0'+self.lineEdit_day.text()
            else:
                self.textEdit_error_display.setText("invalid fields")
            

            if (9<int(self.lineEdit_month.text() )<13)  or (len(self.lineEdit_month.text())>1) :
                month_of_date=self.lineEdit_month.text() 
            elif (1<=int(self.lineEdit_month.text() )<=9)  :
                my_month='0'+self.lineEdit_month.text() 
            else:
                self.textEdit_error_display.setText("invalid fields")

            year_of_date=self.lineEdit_year.text()
            self.lineEdit_date_introduced.setText(day_of_date + '/'+month_of_date+'/'+ year_of_date)

thanks for help

[Gribouillis]

The built-in module datetime is always helpful when handling dates and time

import datetime as dt

def insert_date(self):
    try:
        d = int(self.lineEdit_day.text())
        m = int(self.lineEdit_month.text())
        y = int(self.lineEdit_year.text())
        date = dt.date(y, m, d)
    except ValueError:
        self.textEdit_error_display.setText("invalid fields")
    else:
        self.lineEdit_date_introduced.setText("{:%d/%m/%Y}".format(date))

[atlass218]

thanks for answer.

I have testing the code. It's working for me but :
when I write an incorrect date I have an error dispalyed at textEdit_error_display
if then I correct the date entered previously; the error message displays on textEdit_error_display, does not automatically clear
to solve this problematic I added this line of code :

 self.textEdit_error_display.setText("")

the complete code is :

import datetime as dt
 
def insert_date(self):
    try:
        d = int(self.lineEdit_day.text())
        m = int(self.lineEdit_month.text())
        y = int(self.lineEdit_year.text())
        date = dt.date(y, m, d)
    except ValueError:
        self.textEdit_error_display.setText("invalid fields")
    else:
        self.lineEdit_date_introduced.setText("{:%d/%m/%Y}".format(date))
		self.textEdit_error_display.setText("")

thanks for the code that helped me find a solution to my problem