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How to check if the user can go back in browser history or not
I want using JavaScript to see if there is history or not, I mean if the back button is available on the browser or not.
18...
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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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
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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).
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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...
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...
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
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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...