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Detecting an undefined object property
...operty value is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associa...
Debug.Assert vs Exception Throwing
...t how and when to use assertions, and I understood them well. But still, I don't understand what kind of motivation should drive me to use Debug.Assert instead of throwing a plain exception. What I mean is, in .NET the default response to a failed assertion is to "stop the world" and display a mes...
In jQuery, how do I select an element by its name attribute?
...
This should do it, all of this is in the documentation, which has a very similar example to this:
$("input[type='radio'][name='theme']").click(function() {
var value = $(this).val();
});
I should also note you have multiple identi...
Java EE 6 @javax.annotation.ManagedBean vs. @javax.inject.Named vs. @javax.faces.ManagedBean
...
First of all let me do some clarifications:
Managed bean definition : generally a managed bean is an object that its life cycle (construction, destruction, etc) is managed by a container.
In Java ee we have many containers that manage life cyc...
What is the difference between const_iterator and non-const iterator in the C++ STL?
...
const_iterators don't allow you to change the values that they point to, regular iterators do.
As with all things in C++, always prefer const, unless there's a good reason to use regular iterators (i.e. you want to use the fact that they're...
HTML5 Canvas 100% Width Height of Viewport?
... to run your draw loop within a function that resizes the canvas to the window.innerHeight and window.innerWidth.
Example: http://jsfiddle.net/jaredwilli/qFuDr/
HTML
<canvas id="canvas"></canvas>
JavaScript
(function() {
var canvas = document.getElementById('canvas'),
...
How do I concatenate const/literal strings in C?
...
@psihodelia: Also don't forget that spoons are much better than forks! so be sure to always use a spoon!
– Brian R. Bondy
May 12 '10 at 13:13
...
Writing data into CSV file in C#
...
UPDATE
Back in my naïve days, I suggested doing this manually (it was a simple solution to a simple question), however due to this becoming more and more popular, I'd recommend using the library CsvHelper that does all the safety checks, etc.
CSV is way more compl...
Is < faster than
...iled with $ gcc -m32 -S -masm=intel test.c
if (a < b) {
// Do something 1
}
Compiles to:
mov eax, DWORD PTR [esp+24] ; a
cmp eax, DWORD PTR [esp+28] ; b
jge .L2 ; jump if a is >= b
; Do something 1
.L2:
And
...
How to check if a specified key exists in a given S3 bucket using Java
..., Amazon will prevent you from checking for the presence of the key if you dont have ListBucket access. Just knowing whether a key is present or not, will also suffice for malicious users in some cases. Hence unless they have ListBucket access they will not be able to do so.
...