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C# vs Java generics [duplicate]
...ompiled classes are not actually generic. They compile down to Object and casts. In effect Java generics are a compile time artifact and can easily be subverted at runtime.
C# on the other hand, by virtue of the CLR, implement generics all they way down to the byte code. The CLR took several b...
Entity Framework - Include Multiple Levels of Properties
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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...
What does void mean in C, C++, and C#?
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Not disagreeing, but an additional use of void is in the "cast to void" trick to suppress warnings for unused values. It's a bit of a stretch since it doesn't really correspond with how the compiler interprets things, but you can interpret that to mean "I'm using this value to do no...
Why should I use a pointer rather than the object itself?
...m (especially when using IDEs or text editors that show the signature of a selected functions). Also, const&.
– JAB
Mar 3 '14 at 16:04
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How do I check for nulls in an '==' operator overload without infinite recursion?
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Cast to object in the overload method:
public static bool operator ==(Foo foo1, Foo foo2) {
if ((object) foo1 == null) return (object) foo2 == null;
return foo1.Equals(foo2);
}
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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...
convert an enum to another type of enum
...), value.ToString());
If you mean by numeric value, you can usually just cast:
Enum2 value2 = (Enum2)value;
(with the cast, you might want to use Enum.IsDefined to check for valid values, though)
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Why should I care that Java doesn't have reified generics?
... There is absolutely no need for reification to be able to do that. Method selection is done at compile time when the compile-time type information is available.
– Tom Hawtin - tackline
Dec 18 '09 at 13:25
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SQL Server Text type vs. varchar data type [closed]
...ts in your database
If you do not search on the value of the column
If you select this column rarely and do not join on it.
VARCHAR is good:
If you store little strings
If you search on the string value
If you always select it or use it in joins.
By selecting here I mean issuing any queries that ...
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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