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Finding the direction of scrolling in a UIScrollView?
...ection can change several times over the course of a gesture. For example, if you have a scroll view with paging turned on and the user swipes to go to the next page, the initial direction could be rightward, but if you have bounce turned on, it will briefly be going in no direction at all and then ...
How do I check if a type provides a parameterless constructor?
I'd like to check if a type that is known at runtime provides a parameterless constructor. The Type class did not yield anything promising, so I'm assuming I have to use reflection?
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How do I check to see if a value is an integer in MySQL?
...tions to create integers from values, but is there any way to check to see if a value is an integer? Something like is_int() in PHP is what I am looking for.
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How do I do a Date comparison in Javascript? [duplicate]
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if (date1.getTime() > date2.getTime()) {
alert("The first date is after the second date!");
}
Reference to Date object
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Is there any performance gain in indexing a boolean field?
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Not really. You should think about it like a book. If there were only 3 kinds of words in a book and you index all of them, you would have the same number of index pages as normal pages.
There would be a performance gain if there are relatively few records of one value. For...
Prevent users from submitting a form by hitting Enter
...s
$(document).ready(function() {
$(window).keydown(function(event){
if(event.keyCode == 13) {
event.preventDefault();
return false;
}
});
});
In reading the comments on the original post, to make it more usable and allow people to press Enter if they have completed all the...
ReactJS - Does render get called any time “setState” is called?
...urns true to prevent
subtle bugs when the state is mutated in place, but if you are careful to
always treat the state as immutable and to read-only from props and state
in render() then you can override shouldComponentUpdate with an
implementation that compares the old props and state to the...
JavaScript OR (||) variable assignment explanation
...mind the 'gotcha' which is that the last one will always get assigned even if they're all undefined, null or false. Setting something you know isn't false, null, or undefined at the end of the chain is a good way to signal nothing was found.
– Erik Reppen
Aug ...
Is string in array?
What would be the best way to look in a string[] to see if it contains a element. This was my first shot at it. But perhaps there is something that I am overlooking. The array size will be no larger than 200 elements.
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Why use a ReentrantLock if one can use synchronized(this)?
I'm trying to understand what makes the lock in concurrency so important if one can use synchronized (this) . In the dummy code below, I can do either:
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