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What is a NullReferenceException, and how do I fix it?
.... This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A".
null can have different meanings:
Object variables which are uninitialized and hence poi...
How to initialize all members of an array to the same value?
... array in C (not C++ if that makes a difference). I want to initialize all members of the same value.
23 Answers
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What is the id( ) function used for?
... Python objects.
Is it the same with memory addresses in C?
Conceptually, yes, in that they are both guaranteed to be unique in their universe during their lifetime. And in one particular implementation of Python, it actually is the memory address of the corresponding C object.
If yes, wh...
PHP equivalent of .NET/Java's toString()
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@MarkAmery He gave an answer that implicitly calls the __toString() "Magic Method", but didn't mention that at all. The user asked for an answer that was like the Java toString() method, and in PHP, that's the __toString() function.
– Supuhstar
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What's the Linq to SQL equivalent to TOP or LIMIT/OFFSET?
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Technically, the questioner asked for Linq to SQL, so VB is a viable assumption. That said, ALassek, i'm a c# guy myself and prefer your answer. :-)
– David Alpert
Oct 10 '08 at 16:51
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How to implement an abstract class in ruby?
I know there is no concept of abstract class in ruby. But if at all it needs to be implemented, how to go about it? I tried something like...
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Interface defining a constructor signature?
...ult in Google some 7 years later, I thought I would chip in here - specifically to show how you could use an abstract base class in tandem with your existing Interface and maybe cut down on the amount of refactoring needed in the future for similar situations. This concept has already been hinted a...
Get the latest record from mongodb collection
...1 means order opposite of the one that records are inserted in.
Edit: For all the downvoters, above is a Mongoose syntax,
mongo CLI syntax is: db.collectionName.find({}).sort({$natural:-1}).limit(1)
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How to “properly” create a custom object in JavaScript?
...e result is that in mixed company you will have a mishmash of metaclasses, all behaving slightly differently. What's worse, most JavaScript tutorial material is terrible and serves up some kind of in-between compromise to cover all bases, leaving you very confused. (Probably the author is also confu...
Find a private field with Reflection?
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You can do it just like with a property:
FieldInfo fi = typeof(Foo).GetField("_bar", BindingFlags.NonPublic | BindingFlags.Instance);
if (fi.GetCustomAttributes(typeof(SomeAttribute)) != null)
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