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How to check if IEnumerable is null or empty?
I love string.IsNullOrEmpty method. I'd love to have something that would allow the same functionality for IEnumerable. Is there such? Maybe some collection helper class? The reason I am asking is that in if statements the code looks cluttered if the patter is (mylist != null && mylist....
Why Java needs Serializable interface?
...erialization and having to specify Serializable tag on every object we use is kind of a burden. Especially when it's a 3rd-party class that we can't really change.
...
$(document).ready equivalent without jQuery
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There is a standards based replacement,DOMContentLoaded that is supported by over 98% of browsers, though not IE8:
document.addEventListener("DOMContentLoaded", function(event) {
//do work
});
jQuery's native function is much...
What is the difference between String.slice and String.substring?
Does anyone know what the difference is between these two methods?
8 Answers
8
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Is if(items != null) superfluous before foreach(T item in items)?
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You still need to check if (items != null) otherwise you will get NullReferenceException. However you can do something like this:
List<string> items = null;
foreach (var item in items ?? new List<string>())
{
item.Dump();
}
but you might check performa...
What's the fastest way to convert String to Number in JavaScript?
...t as far as I know.
Number(x);
parseInt(x, 10);
parseFloat(x);
+x;
By this quick test I made, it actually depends on browsers.
http://jsperf.com/best-of-string-to-number-conversion/2
Implicit marked the fastest on 3 browsers, but it makes the code hard to read… So choose whatever you feel lik...
What is mod_php?
...ays of running PHP, when working with Apache :
Using CGI : a PHP process is launched by Apache, and it is that PHP process that interprets PHP code -- not Apache itself
Using PHP as an Apache module (called mod_php) : the PHP interpreter is then kind of "embedded" inside the Apache process : there...
Does anyone have benchmarks (code & results) comparing performance of Android apps written in Xamari
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Yeah, Xamarin's Mono virtual machine is more impressive than Google's Dalvik used in Android. I have tested it with HTC Flyer and Acer Iconia Tab tablets to benchmark the C# port of Android through Mono against Java Dalvik, with the C# implementation of Android...
Efficiency of Java “Double Brace Initialization”?
...rate class file.
The "double brace initialization", as already mentioned, is an anonymous inner class with an instance initialization block, which means that a new class is created for each "initialization", all for the purpose of usually making a single object.
Considering that the Java Virtual M...
How do you represent a graph in Haskell?
It's easy enough to represent a tree or list in haskell using algebraic data types. But how would you go about typographically representing a graph? It seems that you need to have pointers. I'm guessing you could have something like
...