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When saving, how can you check if a field has changed?
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Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharF...
snprintf and Visual Studio 2010
... the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Writes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If buf_size is zero, nothi...
Append text to input field
...might want to write a function:
//Append text to input element
function jQ_append(id_of_input, text){
var input_id = '#'+id_of_input;
$(input_id).val($(input_id).val() + text);
}
After you can just call it:
jQ_append('my_input_id', 'add this text');
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Email validation using jQuery
...ming more common this regex may need modifying .systems and .poker etc are all valid TLDs now but would fail the regex check
– Liath
Sep 5 '14 at 7:35
3
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Adding days to a date in Python
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The previous answers are correct but it's generally a better practice to do:
import datetime
Then you'll have, using datetime.timedelta:
date_1 = datetime.datetime.strptime(start_date, "%m/%d/%y")
end_date = date_1 + datetime.timedelta(days=10)
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How to deep copy a list?
... don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operation on arbitrary Python objects.
See the following snippet -
>>> a = [[1, 2, 3], [4, 5, 6]]...
How do I concatenate two lists in Python?
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@Daniel it will create a new list with a shallow copy of the items in the first list, followed by a shallow copy of the items in the second list. Use copy.deepcopy to get deep copies of lists.
– Daniel G
Apr 19 '12 at 14:51
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Does height and width not apply to span?
...ides no context to indicate that a div is inherently inappropriate semantically.
– Isaac
Mar 22 '10 at 9:45
1
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Facebook API - How do I get a Facebook user's profile image through the Facebook API (without requir
...m/users_unique_url ). How can I accomplish this? Is there a Faceboook API call that fetches a user's profile image URL without the user needing to Allow the application?
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Python assigning multiple variables to same value? list behavior
...the same identical value. Variables have types, identities, addresses, and all kinds of stuff like that.
Names don't have any of that. Values do, of course, and you can have lots of names for the same value.
If you give Notorious B.I.G. a hot dog,* Biggie Smalls and Chris Wallace have a hot dog. ...