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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...
Symfony 2: How do I check if a user is not logged in inside a template?
...any user is logged in.
{% if app.user %}
# user is logged in (any and all users, regardless of ROLE_*)
{% elseif not app.user %}
# user is not logged in (note the `not` in the `elseif` statement)
{% endif %}
Checking authentication status
You can use the is_granted() method to check fo...
HTML-encoding lost when attribute read from input field
...e){
// Create a in-memory element, set its inner text (which is automatically encoded)
// Then grab the encoded contents back out. The element never exists on the DOM.
return $('<textarea/>').text(value).html();
}
function htmlDecode(value){
return $('<textarea/>').html(value).t...
How can I recall the argument of the previous bash command?
Is there a way in Bash to recall the argument of the previous command?
7 Answers
7
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snprintf and Visual Studio 2010
... the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Writes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If buf_size is zero, nothi...
Collection that allows only unique items in .NET?
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If all you need is to ensure uniqueness of elements, then HashSet is what you need.
What do you mean when you say "just a set implementation"? A set is (by definition) a collection of unique elements that doesn't save element ...
Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;
...ing the Java Build Path and seeing this new item, and unchecking the originally-included support library solved the problem for me.
– Tom Pace
Sep 26 '13 at 17:20
9
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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');
...
CoInitialize浅析一 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
... push [ebp+8] ; pvReserved
769B2A2E call _CoInitializeEx@8 ; CoInitializeEx(x,x)
769B2A33 pop ebp
769B2A34 retn 4
可以看到，其中的实现还是比较简单的，它只是简单地调用了CoInitializeEx，将第二个...
Count how many records are in a CSV Python?
...aranteed to be a fixed size, so the only way to count them is to read them all.
– Martijn Pieters♦
Apr 19 '13 at 15:55
1
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