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Django: Get an object form the DB, or 'None' if nothing matches
...get(*args, **kwargs)
except model.DoesNotExist:
return None
Call it like this
foo = get_or_none(Foo, baz=bar)
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How do I see if Wi-Fi is connected on Android?
... does not
support multiple connected networks of the same type. Use
getAllNetworks() and getNetworkInfo(android.net.Network) instead.
NOTE3: public static final int TYPE_WIFI is now deprecated:
This constant was deprecated in API level 28.
Applications should instead use NetworkCapabilit...
How to set up a Subversion (SVN) server on GNU/Linux - Ubuntu [closed]
... would like to act as a Subversion server. Both for myself to commit to locally, and for others remotely. What are the steps required to get this working? Please include steps to:
...
Java: How to get input from System.console()
...Console class to get input from user but a null object is returned when I call System.console() . Do I have to change anything before using System.console?
...
What is stdClass in PHP?
... class, kind of like Object in Java or object in Python (Edit: but not actually used as universal base class; thanks @Ciaran for pointing this out).
It is useful for anonymous objects, dynamic properties, etc.
An easy way to consider the StdClass is as an alternative to associative array. See thi...
How do I check if file exists in jQuery or pure JavaScript?
...n('HEAD', url, false);
http.send();
return http.status!=404;
}
Small changes and it could check for status HTTP status code 200 (success), instead.
EDIT 2: Since sync XMLHttpRequest is deprecated, you can add a utility method like this to do it async:
function executeIfFileExist(src, cal...
Getting attribute using XPath
...
you can use:
(//@lang)[1]
these means you get all attributes nodes with name equal to "lang" and get the first one.
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Moving decimal places over in a double
...
which prints:
12.34
This works because Double.toString(d) performs a small amount of rounding on your behalf, but it is not much. If you are wondering what it might look like without rounding:
System.out.println(new BigDecimal(0.1));
System.out.println(new BigDecimal(x));
prints:
0.100000000...
img tag displays wrong orientation
... Why in the world do images even have orientation metadata? If you really wanted to rotate the picture then wouldn't you just shift around the pixels and swap the width for the height?
– Jack Giffin
Oct 29 '17 at 1:02
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How to turn a String into a JavaScript function call? [duplicate]
...eId) {}. Once we have a reference to a function inside a variable, we can call this function by "calling the variable", i.e. fn(t.parentNode.id), which equals clickedOnItem(t.parentNode.id), which was what the OP wanted.
More full example:
/* Somewhere: */
window.settings = {
/* [..] Other setti...