python - validating date with datetime

Question

I'm am trying to validate a string prompted for the user. This string should be write in the format dd/mm/aaaa and be a valid date. I thought than create a lot of if to check is not be ellegant, so i research and picked-up the datetime way.

import datetime

dataInput = input("Insira sua data de nascimento no formato 'dd/mm/aaaa': ")

ehDataValida = False

def validaData(dataInput) :
    while True :
            try :
                if dataInput != datetime.datetime.strptime(dataInput, "%d/%m/%Y").strftime("%d/%m/%Y") :
                    raise ValueError
                return False
            except ValueError:
                print("erro!")
                dataInput = input("Insira sua data de nascimento no formato 'dd/mm/aaaa': ")
                return dataInput

validaData(dataInput)
print(validaData(dataInput))

It's not working and for each test I found a new bug. What i'm missing? After this, I will dataInput.split('/') and achieve the date in a listData=[dd, mm, yyyy]

https://stackoverflow.com/questions/16870663/how-do-i-validate-a-date-string-format-in-python — cs95, Mar 23 '18 at 03:49
i saw this topic and many others but i can't figure out a solution. what I'm tryng to implement was found in this topic, but i not reach the behavior yet: just `check`, and in case of `error`, `prompt` the user again and, so , if validated, `update` the `data_input var` ... — Lucas Maraal, Mar 23 '18 at 03:54
try the modified answer @Lucas Maraal .. your input is being read as integer, eg: if you input 12/2/1992, it is performing division operation as ((12 / 2) / 1992) which results in zero — Vipin Mohan, Mar 23 '18 at 04:10

Vipin Mohan · Accepted Answer · 2018-03-23T04:23:57.363

0

Your input is being read as integer, eg: if you input 12/2/1992, it is performing division operation as ((12 / 2) / 1992) which results in zero. Use raw_input instead

import datetime

dataInput = raw_input("Insira sua data de nascimento no formato 'dd/mm/aaaa': ")

ehDataValida = False

def validaData(dataInput) :
    try:
        datetime.datetime.strptime(dataInput, '%d/%m/%y')
    except ValueError:
        raise ValueError("Insira sua data de nascimento no formato 'dd/mm/aaaa': ")

validaData(dataInput)

Try this. It should work

while True:
    try:
        dataInput = raw_input("Insira sua data de nascimento no formato 'dd/mm/aaaa': ")
        date_formatted = datetime.datetime.strptime(dataInput, '%d/%m/%y')
        break
    except ValueError:
        raise ValueError("Insira sua data de nascimento no formato 'dd/mm/aaaa': ")

edited Mar 23 '18 at 04:23

answered Mar 23 '18 at 03:54

Vipin Mohan

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could you be kind enough to translate 'Insira sua data de nascimento no formato 'dd/mm/aaaa': ' , I'm assuming it means wrong format , please try again, If you are trying to create an input prompt after exception error, No,, then my code is incomplete ,my code merely raises an error message. – Vipin Mohan Mar 23 '18 at 04:17
Yeah, this works. Just a thing: i think in Python do not have `raw_input`, but doing `dataInput = str(input("Insira sua data de nascimento no formato 'dd/mm/aaaa': "))` Works. Thank you. (the translate is: Insert you bithday's date in the format 'dd/mm/yyyy') if you want to see: https://ideone.com/XfU92V – Lucas Maraal Mar 23 '18 at 04:29
@LucasMaraal look at the edits, it should loop until it is successfull, – Vipin Mohan Mar 23 '18 at 04:31
i marked, but i tried this last edit solution and not woks... the another one works. – Lucas Maraal Mar 23 '18 at 05:28
let me check once more, – Vipin Mohan Mar 23 '18 at 05:47

python - validating date with datetime

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