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(this == null) in C#!
...spec (section 7.5.7), you shouldn't be able to access this in that context and the ability to do so in C# 3.0 compiler is a bug. C# 4.0 compiler is behaving correctly according to the spec (even in Beta 1, this is a compile time error):
§ 7.5.7 This access
A this-access consists of the res...
MySQL select where column is not empty
...g:
select phone, phone2
from jewishyellow.users
where phone like '813%' and phone2<>''
Note that NULL value is interpreted as false.
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Getting the path of the home directory in C#?
...Reading environment variables is actually very portable to do (across Unix and Windows), so I'm not sure why the poster wanted to not do it.
Edited to add: For crossplatform (Windows/Unix) C#, I'd read $HOME on Unix and OSX and %HOMEDRIVE%%HOMEPATH% on Windows.
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Why catch and rethrow an exception in C#?
...about where the exception actually was created.
Second, if you just catch and re-throw like that, I see no added value, the code example above would be just as good (or, given the throw ex bit, even better) without the try-catch.
However, there are cases where you might want to catch and rethrow a...
Worst security hole you've seen? [closed]
...opping cart. The software properly calculated the total cost as .1 * cost, and the human packing the order simply glossed over the odd "." in front of the quantity to pack :)
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Why no love for SQL? [closed]
I've heard a lot lately that SQL is a terrible language, and it seems that every framework under the sun comes pre-packaged with a database abstraction layer.
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SQL “select where not in subquery” returns no results
...emantically the same.
When it is nullable, NOT IN is different, since IN (and, therefore, NOT IN) return NULL when a value does not match anything in a list containing a NULL.
This may be confusing but may become more obvious if we recall the alternate syntax for this:
common_id = ANY
(
SELECT c...
Avoiding SQL injection without parameters
...ametrized sql queries in our code. We have two sides in the discussion: Me and some others that say we should always use parameters to safeguard against sql injections and the other guys that don't think it is necessary. Instead they want to replace single apostrophes with two apostrophes in all str...
C# : 'is' keyword and checking for Not
...ublic static bool IsA<T>(this object obj) {
return obj is T;
}
and then use it to:
if (!child.IsA<IContainer>())
And you could follow on your theme:
public static bool IsNotAFreaking<T>(this object obj) {
return !(obj is T);
}
if (child.IsNotAFreaking<IContainer&g...
Can I use break to exit multiple nested 'for' loops?
...
AFAIK, C++ doesn't support naming loops, like Java and other languages do. You can use a goto, or create a flag value that you use. At the end of each loop check the flag value. If it is set to true, then you can break out of that iteration.
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