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Check, using jQuery, if an element is 'display:none' or block on click
...hidden');
visibleElements = $(':visible');
To check particular element.
if($('#yourID:visible').length == 0)
{
}
Elements are considered visible if they consume space in the document.
Visible elements have a width or height that is greater than zero,
Reference
You can also use is() wi...
How to determine if object is in array [duplicate]
I need to determine if an object already exists in an array in javascript.
11 Answers
...
What is the proper way to check if a string is empty in Perl?
I've just been using this code to check if a string is empty:
6 Answers
6
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Why is there no logical xor in JavaScript?
...ul, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables you can mimic XOR with:
if (a != b)
With two arbitrary variables you could use ! to coerce them to boolean values and then use the same trick:
if (!a != !b)
That's pretty obscure though...
Default value of a type at Runtime [duplicate]
... only need to account for two cases:
object GetDefaultValue(Type t)
{
if (t.IsValueType)
return Activator.CreateInstance(t);
return null;
}
(Because value types always have a default constructor, that call to Activator.CreateInstance will never fail).
...
Checking if a key exists in a JavaScript object?
How do I check if a particular key exists in a JavaScript object or array?
22 Answers
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Check number of arguments passed to a Bash script
I would like my Bash script to print an error message if the required argument count is not met.
10 Answers
...
Is it better in C++ to pass by value or pass by constant reference?
...ecially true before the existence of move semantics. The reason is simple: if you passed by value, a copy of the object had to be made and, except for very small objects, this is always more expensive than passing a reference.
With C++11, we have gained move semantics. In a nutshell, move semantics...
ProcessStartInfo hanging on “WaitForExit”? Why?
...
The problem is that if you redirect StandardOutput and/or StandardError the internal buffer can become full. Whatever order you use, there can be a problem:
If you wait for the process to exit before reading StandardOutput the process can bloc...
How can the Euclidean distance be calculated with NumPy?
...
If OP wanted to calculate the distance between an array of coordinates it is also possible to use scipy.spatial.distance.cdist.
– mnky9800n
May 2 '17 at 9:47
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