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jQuery: checking if the value of a field is null (empty)
... "NULL". You want to check if it's an empty string instead:
if ($('#person_data[document_type]').val() != ''){}
or:
if ($('#person_data[document_type]').val().length != 0){}
If you want to check if the element exist at all, you should do that before calling val:
var $d = $('#person_data[docum...
.NET: Which Exception to Throw When a Required Configuration Setting is Missing?
...
The ConfigurationElement class (which is the base class of many config-related classes, like ConfigurationSection) has a method called OnRequiredPropertyNotFound (there are other helper methods too). You can maybe call those.
The OnRequiredPropertyNotFound is implemen...
How to check for an active Internet connection on iOS or macOS?
... print("Reachable via Cellular")
}
}
reachability.whenUnreachable = { _ in
print("Not reachable")
}
do {
try reachability.startNotifier()
} catch {
print("Unable to start notifier")
}
Objective-C
1) Add SystemConfiguration framework to the project but don't worry about includi...
Check if pull needed in Git
...reduce it to a yes/no answer. However, if you're prepared to do a pull --rebase then you can treat "local is behind" and "local has diverged" as "need to pull", and the other two as "don't need to pull".
You can get the commit id of any ref using git rev-parse <ref>, so you can do this for ma...
Easiest way to check for an index or a key in an array?
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I solved in this way: if test "${myArray['key_or_index']+isset}"; then echo "yes"; else echo "no"; fi; It seems to me the simplest way and it applies to indexed and associative arrays. Thank you
– Luca Borrione
Nov 4 '12 at 19:13
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What does this square bracket and parenthesis bracket notation mean [first1,last1)?
... offset depending on which field are you in:
Mathematics tends to be one-based.
Certain programming languages tends to be zero-based, such as C, C++, Javascript, Python, while other languages such as Mathematica, Fortran, Pascal are one-based.
These differences can lead to subtle fence post er...
Do checkbox inputs only post data if they're checked?
...lt. However, if you are not interested in the value, just use:
if (isset($_POST['the_checkbox'])){
// name="the_checkbox" is checked
}
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What in the world are Spring beans?
...dia I should say "instance objects" instead: en.wikipedia.org/wiki/Instance_(computer_science)
– Elias Dorneles
Oct 5 '18 at 16:03
2
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How to find index of list item in Swift?
...'m receiving: Binary operator '===' cannot be applied to operands of type '_' and 'Post' , Post is my struct... any idea?
– David Seek
Dec 21 '16 at 17:05
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Octave-Gnuplot-AquaTerm error: set terminal aqua enhanced title “Figure 1”…unknown terminal type"
...
I had to add setenv("GNUTERM","X11") to OCTAVE_HOME/share/octave/site/m/startup/octaverc (OCTAVE_HOME usually is /usr/local) to make it work permanently.
Solution found and more details on: http://www.mac-forums.com/forums/os-x-apps-games/242997-plots-octave-dont-work.h...