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How do I get the base URL with PHP?
... XAMPP on Windows Vista. In my development, I have http://127.0.0.1/test_website/ .
22 Answers
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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...
Swift: Testing optionals for nil
...let
guard let can do similar things. It's main purpose is to make it logically more reasonable. It's like saying Make sure the variable is not nil, otherwise stop the function. guard let can also do extra condition checking as if let.
The differences are that the unwrapped value will be available ...
Position a CSS background image x pixels from the right?
...ected as the "Correct answer". According to MDN it's supported in IE9+ and all other browsers, which is great! developer.mozilla.org/en-US/docs/Web/CSS/…
– fregante
Sep 27 '13 at 0:16
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Java Keytool error after importing certificate , “keytool error: java.io.FileNotFoundException & Acc
...mmand prompt in administrator mode. If not, you can also go to start -> all programs -> accessories -> right click command prompt and click 'run as administrator'.
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Changing every value in a hash in Ruby
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@Andrew Marshall Right you are, thanks. In Ruby 1.8, Hash.[] doesn't accept an array of array pairs, it requires an even number of direct arguments (hence the splat up front).
– Phrogz
Mar 4 '11 at 3...
Java synchronized method lock on object, or method?
... anyway. That's a bit misleading. Synchronizing on the method is functionally equivalent to having a synchronized (this) block around the body of the method. The object "this" doesn't become locked, rather the object "this" is used as the mutex and the body is prevented from executing concurrentl...
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...
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 ...
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...