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In .NET, which loop runs faster, 'for' or 'foreach'?
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Patrick Smacchia blogged about this last month, with the following conclusions:
for loops on List are a bit more than 2 times cheaper than foreach
loops on List.
Looping on array is around 2 times cheaper than looping on List.
As a consequence, looping on array...
Identity increment is jumping in SQL Server database
... of my tables Fee in column "ReceiptNo" in SQL Server 2012 database identity increment suddenly started jumping to 100s instead of 1 depending on the following two things.
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What is the difference between MVC and MVVM? [closed]
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MVC/MVVM is not an either/or choice.
The two patterns crop up, in different ways, in both ASP.Net and Silverlight/WPF development.
For ASP.Net, MVVM is used to two-way bind data within views. This is usually a client-side implementation (e.g. us...
Why do most fields (class members) in Android tutorial start with `m`?
I know about camel case rules, but I'm confused with this m rule. What does it stand for? I'm a PHP developer. "We" use first letters of variables as indication of type, like 'b' for boolean, 'i' for integer and so on.
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How to parse a string to an int in C++?
...at: stoi, stol, stoll, stoul and so on.
int myNr = std::stoi(myString);
It will throw an exception on conversion error.
Even these new functions still have the same issue as noted by Dan: they will happily convert the string "11x" to integer "11".
See more: http://en.cppreference.com/w/cpp/stri...
Why 0 is true but false is 1 in the shell?
The above will output 1 , which is contradictory with all other programming languages I know.
10 Answers
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Unnamed/anonymous namespaces vs. static functions
A feature of C++ is the ability to create unnamed (anonymous) namespaces, like so:
11 Answers
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Which HTML elements can receive focus?
I'm looking for a definitive list of HTML elements which are allowed to take focus, i.e. which elements will be put into focus when focus() is called on them?
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How to change the session timeout in PHP?
...lutely certain that no session ever will survive after X minutes of inactivity.
If relaxing this requirement a little is acceptable and you are fine with placing a lower bound instead of a strict limit to the duration, you can do so easily and without writing custom logic.
Convenience in relaxed env...
What does the Q_OBJECT macro do? Why do all Qt objects need this macro?
I just started using Qt and noticed that all the example class definitions have the macro Q_OBJECT as the first line. What is the purpose of this preprocessor macro?
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