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Test if object implements interface
...or is null safe (the code you posted isn't).
instanceof is the built-in, compile-time safe alternative to Class#isInstance(Object)
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How is std::function implemented?
...rces I have found, a lambda expression is essentially implemented by the compiler creating a class with overloaded function call operator and the referenced variables as members. This suggests that the size of lambda expressions varies, and given enough references variables that size can be arbit...
MySQL, better to insert NULL or empty string?
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How many characters can UTF-8 encode?
..., Coptic, Armenian, Hebrew, Arabic, Syriac and Tāna alphabets, as well as Combining Diacritical Marks.
Three bytes are needed for characters in the rest of the Basic Multilingual Plane, which contains virtually all characters in common use[12] including most Chinese, Japanese and Korean [CJK] ...
getting date format m-d-Y H:i:s.u from milliseconds
...s",$date_array[1]);
echo "Date: $date:" . $date_array[0]."<br>";
Recommended and use dateTime() class from referenced:
$t = microtime(true);
$micro = sprintf("%06d",($t - floor($t)) * 1000000);
$d = new DateTime( date('Y-m-d H:i:s.'.$micro, $t) );
print $d->format("Y-m-d H:i:s.u"); // ...
ASP.NET Identity DbContext confusion
A default MVC 5 App comes with this piece of code in IdentityModels.cs - this piece of code is for all the ASP.NET Identity operations for the default templates:
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What's the difference between session.Merge and session.SaveOrUpdate?
...ance
the persistent instance is returned
the given instance does not become associated with the session, it
remains detached
You should use Merge() if you are trying to update objects that were at one point detached from the session, especially if there might be persistent instances of t...
When is it appropriate to use C# partial classes?
...ner would spit out all of the code inside of a region with strongly worded comments about not modifying the code. It had to insert all sorts of heuristics to find the generated code for later processing. Now it can simply open the designer.cs file and have a high degree of confidence that it contai...
How to create a directory if it doesn't exist using Node.js?
...when it tries writing to files in it. The answer by @josh3736 is much more complete and totally underrated.
– Benni
Jan 15 '19 at 7:59
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