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Create a list from two object lists with linq
...ite a lot to this:
list1.Concat(list2)
.ToLookup(p => p.Name)
.Select(g => g.Aggregate((p1, p2) => new Person
{
Name = p1.Name,
Value = p1.Value,
Change = p2.Value - p1.Value
}));
Although this won't error in the case where you have duplicate na...
Reflection - get attribute name and value on property
...
I was hoping that I won't have to cast the attribute.
– developerdoug
Jul 9 '11 at 22:14
...
What is the difference between IQueryable and IEnumerable?
...es, meaning the custom query logic it receives, e.g., a predicate or value selector, is in the form of an expression tree instead of a delegate to a method.
IEnumerable<T> is great for working with sequences that are iterated in-memory, but
IQueryable<T> allows for out-of memory things ...
Why is sizeof considered an operator?
...fine. They're often seen, firstly because they're needed as part of a type cast expression, and secondly because sizeof has very high precedence, so sizeof a + b isn't the same as sizeof (a+b). But they aren't part of the invocation of sizeof, they're part of the operand.
You can't take the address ...
Pass An Instantiated System.Type as a Type Parameter for a Generic Class
...amic is still rooted to a strongly typed language the run time binder will select the appropriate Markdown method. If there is no exact type matches, it will look for an object parameter method and if neither match a runtime binder exception will be raised alerting that no method matches.
The obvio...
Is null check needed before calling instanceof?
...lue of the RelationalExpression is
not null and the reference could be
cast to the ReferenceType
without raising a ClassCastException.
Otherwise the result is false."
So if the operand is null, the result is false.
...
How to get the error message from the error code returned by GetLastError()?
... pointer? But passing it the pointer's address (pointer-to-a-pointer), but casting it to a regular pointer... Win32 weirdness. Thanks for the heads up, fixed it in my own code base (and my answer). Very subtle catch.
– Jamin Grey
Jan 11 '14 at 1:45
...
SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range valu
...table). In comment you said you want it in yyyy-mm-dd format. So, try this SELECT CONVERT(char(10), GetDate(),126). Just replace GETDATE() with necessary value.
– Mahe
Dec 30 '13 at 15:29
...
Is there a Python equivalent to Ruby's string interpolation?
...
@Caste see here: docs.python.org/library/stdtypes.html#string-formatting and post a follow up comment if you need any more details
– mikej
Dec 15 '10 at 13:59
...
How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?
...trick if it is a BOOL parameter.
Pass nil for NO and self for YES. nil is cast to the BOOL value of NO. self is cast to the BOOL value of YES.
This approach breaks down if it is anything other than a BOOL parameter.
Assuming self is a UIView.
//nil will be cast to NO when the selector is perform...