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Why are Where and Select outperforming just Select?
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+1 for being the only answer (so far) that actually addresses the question, doesn't guess the answer and doesn't just generate "me too!" statistics.
– Binary Worrier
Aug 20 '13 at 13:21
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Firing a double click event from a WPF ListView item using MVVM
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Please, code behind is not a bad thing at all. Unfortunately, quite a lot people in the WPF community got this wrong.
MVVM is not a pattern to eliminate the code behind. It is to separate the view part (appearance, animations, etc.) from the logic part (workflow). F...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
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You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
What is the purpose of a stack? Why do we need it?
...there a transfer from stack to memory or "storing"? Why not just have them all placed in the memory?
MSIL is a "virtual machine" language. Compilers like the C# compiler generate CIL, and then at runtime another compiler called the JIT (Just In Time) compiler turns the IL into actual machine code ...
Create subdomains on the fly with .htaccess (PHP)
...ches[1])) {
$subdomain = $matches[1];
}
I have used regex here to to allow for people hitting your site via www.subdomain.example.org or subdomain.example.org.
If you never anticipate having to deal with www. (or other subdomains) then you could simply use a substring like so:
$subdomain = s...
How to sort a dataframe by multiple column(s)
...as speedy as the base R commands with their convoluted machinations. Typically brilliant Hadley Wickham work. My only gripe with it is that it breaks the standard R nomenclature where sorting objects get called by sort(object), but I understand why Hadley did it that way due to issues discussed in...
Safest way to convert float to integer in python?
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All integers that can be represented by floating point numbers have an exact representation. So you can safely use int on the result. Inexact representations occur only if you are trying to represent a rational number with a ...
Why use a prime number in hashCode?
...ly be determined by the least significant entry (the one not multiplied at all). Similar entries will collide. Not good for a hash function.
31 is a large enough prime that the number of buckets is unlikely to be divisible by it (and in fact, modern java HashMap implementations keep the number of b...
Change string color with NSAttributedString?
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There is no need for using NSAttributedString. All you need is a simple label with the proper textColor. Plus this simple solution will work with all versions of iOS, not just iOS 6.
But if you needlessly wish to use NSAttributedString, you can do something like this:
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Real mouse position in canvas [duplicate]
... evt.clientX - rect.left,
y: evt.clientY - rect.top
};
}
Just call it from your event with the event and canvas as arguments. It returns an object with x and y for the mouse positions.
As the mouse position you are getting is relative to the client window you'll have to subtract the pos...