Setting the time on a datetimefield

[Tim Sawyer]

Hi Folks,

I have an object with a model.DateTimeField on it. For various reasons, I
need to set the time portion of this field to 23:59 when I populate it from a
form.

datetime = models.DateTimeField()

How can I do this? I've tried

self.datetime = pForm.cleaned_data['datetime']
self.datetime.replace(hour=23, minute=59)

but hour isn't accepted as a parameter to replace.

I'm also confused as to how the DateTimeField maps on to a python datetime
object, can anyone educate me?

Thanks,

Tim.

[Rajesh Dhawan]

Hi Tim,

> I have an object with a model.DateTimeField on it. For various reasons, I
> need to set the time portion of this field to 23:59 when I populate it from a
> form.
>
> datetime = models.DateTimeField()
>
> How can I do this? I've tried
>
> self.datetime = pForm.cleaned_data['datetime']
> self.datetime.replace(hour=23, minute=59)

The replace method here returns a new instance of a datetime object --
it's not an in-place replace. This should work:

self.datetime = self.datetime.replace(hour=23, minute=59)

That works both when datetime is a forms.DateTimeField or
models.DateTimeField.

>
> but hour isn't accepted as a parameter to replace.

It is. Are you getting a Python error when you do that?

>
> I'm also confused as to how the DateTimeField maps on to a python datetime
> object, can anyone educate me?

You can directly assign a Python datetime object to a
models.DateTimeField.

-Rajesh D

[Tim Sawyer]

On Monday 14 Jul 2008, Rajesh Dhawan wrote:
> The replace method here returns a new instance of a datetime object --
> it's not an in-place replace. This should work:
>
> self.datetime = self.datetime.replace(hour=23, minute=59)

Hmm, that seemed to make sense to me too, though with my Java background I
wasn't sure. I get:

Exception Value: 'hour' is an invalid keyword argument for this function

on

self.datetime = self.datetime.replace(hour=23, minute=59)

self.datetime is defined as:

datetime = models.DateTimeField()

Cheers,

Tim.

[Rajesh Dhawan]

Strange...I just ran a few tests on a model field like that and it all
worked perfectly.

Can you dpaste your relevant code?

Also, if you print type(self.datetime), do you get the type as
datetime.datetime or something else?

[Tim Sawyer]

Sussed it.

In my code, I did this:

self.datetime = pForm.cleaned_data['datetime']

the datetime parameter passed from the form only contained the date, with no
time, so I assume the value in datetime then was only a date.

I've sorted my problem using the following code:

self.datetime = datetime(self.datetime.year, self.datetime.month,
self.datetime.day, 23, 59)

Thanks for your help,

Tim.

[Arien]

On Tue, Jul 15, 2008 at 4:57 AM, Tim Sawyer <list....@calidris.co.uk> wrote:
> In my code, I did this:
>
> self.datetime = pForm.cleaned_data['datetime']
>
> the datetime parameter passed from the form only contained the date, with no
> time, so I assume the value in datetime then was only a date.

This shouldn't happen: a DateTimeField normalizes to a
datetime.datetime object. Are you sure you're not using a DateField
in your form?

Arien

[Tim Sawyer]

Well spotted.

In my form I have:

datetime =
forms.DateField(widget=forms.TextInput({'class' : 'date-pick'}),label="Available
date")

yet it's a DateTimeField in the model.

This means that the reason that the value fetched from the form is only a date
is because of the type in the form. Assigning this date only value from the
form to the model attribute means I can't use replace(hour=23) on it any
more. I don't really understand why, but I'm sure there's a logical
explanation!

Tim.

[Arien]

On Tue, Jul 15, 2008 at 7:25 AM, Tim Sawyer <list....@calidris.co.uk> wrote:
> In my form I have:
>
> datetime =
> forms.DateField(widget=forms.TextInput({'class' : 'date-pick'}),label="Available
> date")
>
> yet it's a DateTimeField in the model.

Why not use a DateTimeField in your form and change the widget
instead? For example:

datetime = forms.DateTimeField(
widget=forms.DateTimeInput(format='%Y-%m-%d', attrs={'class' :
'date-pick'}),
label="Available date"
)

(Note the attrs={...} for the class.)

> This means that the reason that the value fetched from the form is only a date
> is because of the type in the form. Assigning this date only value from the
> form to the model attribute means I can't use replace(hour=23) on it any
> more. I don't really understand why, but I'm sure there's a logical
> explanation!

The logical explanation is that adjusting the hour of a date doesn't
make sense, because a date doesn't have any hour. ;-)

Arien