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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...
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
...
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
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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 do you tell if a string contains another string in POSIX sh?
I want to write a Unix shell script that will do various logic if there is a string inside of another string. For example, if I am in a certain folder, branch off. Could someone please tell me how to accomplish this? If possible I would like to make this not shell specific (i.e. not bash only) but i...
List comprehension with if statement
...
You got the order wrong. The if should be after the for (unless it is in an if-else ternary operator)
[y for y in a if y not in b]
This would work however:
[y if y not in b else other_value for y in a]
...
Why '&&' and not '&'?
...at the evaluation is canceled as soon as the result is clear.
Example:
if(CanExecute() && CanSave())
{
}
If CanExecute returns false, the complete expression will be false, regardless of the return value of CanSave. Because of this, CanSave is not executed.
This is very handy in the f...