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IllegalArgumentException or NullPointerException for a null parameter? [closed]
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It seems like an IllegalArgumentException is called for if you don't want null to be an allowed value, and the NullPointerException would be thrown if you were trying to use a variable that turns out to be null.
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Can JavaScript connect with MySQL?
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I wouldn't call that "mix JS with PHP", though. What you might do is let PHP Code generate JavaScript Code/Data(json, e.g.) that it has retrieved from MySQL in advance. Or you might use PHP on a server to provide an http(json/REST/SOAP...
Why does .NET foreach loop throw NullRefException when collection is null?
...r is "because that's the way the compiler designers designed it." Realistically, though, your collection object is null, so there's no way for the compiler to get the enumerator to loop through the collection.
If you really need to do something like this, try the null coalescing operator:
int[] a...
How to save MailMessage object to disk as *.eml or *.msg file
...eeded to add the <network host="...", etc. in addition to what Ryan provided.
– Steven Rogers
Jul 7 '11 at 20:42
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How to return a result from a VBA function
... also worth mentioning that the behaviour of the function differs when you call it from a spreadsheet, compared with calling it from another VBA function or Sub.
– Doug Jenkins
Sep 13 '18 at 23:08
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TSQL - How to use GO inside of a BEGIN .. END block?
I am generating a script for automatically migrating changes from multiple development databases to staging/production. Basically, it takes a bunch of change-scripts, and merges them into a single script, wrapping each script in a IF whatever BEGIN ... END statement.
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How to check if an element does NOT have a specific class?
... of DOM elements just as easy as we can on single objects. Your answer provides just that solution. +1
– Stijn de Witt
Sep 28 '12 at 9:27
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What is the copy-and-swap idiom?
...e assignment operator in terms of itself!
(Not only that, but unqualified calls to swap will use our custom swap operator, skipping over the unnecessary construction and destruction of our class that std::swap would entail.)
An in-depth explanation
The goal
Let's consider a concrete case. We w...
Multiple Inheritance in C#
...ould use the Extension Methods feature added to C# 3.0 to further simplify calling methods on those implied properties, eg:
public interface ISteerable { SteeringWheel wheel { get; set; } }
public interface IBrakable { BrakePedal brake { get; set; } }
public class Vehicle : ISteerable, IBrakable
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Determine if a String is an Integer in Java [duplicate]
...ittle more expensive (you have to create a Scanner object, which in a critically-tight loop you don't want to do. But it generally shouldn't be too much more expensive, so for day-to-day operations it should be pretty reliable.
public static boolean isInteger(String s, int radix) {
Scanner sc =...