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Entity Framework - Include Multiple Levels of Properties
...
For EF 6
using System.Data.Entity;
query.Include(x => x.Collection.Select(y => y.Property))
Make sure to add using System.Data.Entity; to get the version of Include that takes in a lambda.
For EF Core
Use the new method ThenInclude
query.Include(x => x.Collection)
.ThenIncl...
Double not (!!) operator in PHP
... you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
return (bool)$row;
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Java: Instanceof and Generics
...(Object o) {
try {
abstractMethod((T) o);
} catch (ClassCastException e) {
//...
You are casting the object to T (your generic type), just to fool the compiler. Your cast does nothing at runtime, but you will still get a ClassCastException when you try to pass the wrong type of...
List of Delphi language features and version in which they were introduced/deprecated
...dynamic arrays to a pointer using the @ operator is only allowed when hard-casting the array.
More flexible namespace resolution of unit names
Delphi 10.1 Berlin
Native support for Utf8String and RawByteString type on all platforms
The [weak], [unsafe] and [volatile] attributes are support...
Signed to unsigned conversion in C - is it always safe?
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As was previously answered, you can cast back and forth between signed and unsigned without a problem. The border case for signed integers is -1 (0xFFFFFFFF). Try adding and subtracting from that and you'll find that you can cast back and have it be correct.
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Validation failed for one or more entities while saving changes to SQL Server Database using Entity
...trings.
var errorMessages = ex.EntityValidationErrors
.SelectMany(x => x.ValidationErrors)
.Select(x => x.ErrorMessage);
// Join the list to a single string.
var fullErrorMessage = string.Join("; ", errorMessages);
// Combine the origin...
What is std::move(), and when should it be used?
...the object has type "rvalue-reference" (Type &&).
std::move() is a cast that produces an rvalue-reference to an object, to enable moving from it.
It's a new C++ way to avoid copies. For example, using a move constructor, a std::vector could just copy its internal pointer to data to the new...
What would be C++ limitations compared C language? [closed]
..._t) );
To make it compile as C++ you have to write:
foo_t* foo = static_cast<foo_t*>( malloc ( sizeof(foo_t) ) );
which isn't valid C any more. (you could use the C-style cast, it which case it would compile in C, but be shunned by most C++ coding standards, and also by many C programmers...
What is Type-safe?
...hon)), some of them will actually give you a runtime error on invalid type casting.
While its convenient, it opens you up to a lot of errors that can be easily missed, and only identified by testing the running program. Personally, I prefer to have my compiler tell me if I made that mistake.
Now, ...
What's the strangest corner case you've seen in C# or .NET? [closed]
... All the methods are overridden, except GetType() which can't be; so it is cast (boxed) to object (and hence to null) to call object.GetType()... which calls on null ;-p
Update: the plot thickens... Ayende Rahien threw down a similar challenge on his blog, but with a where T : class, new():
priv...