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Nullable type issue with ?: Conditional Operator
...ving that:
First is to make null compatible with DateTime (for instance, cast null to DateTime? as the gentleman with 70 upvotes suggests, or cast null to Object or to ValueType).
The second is to make the DateTime compatible with null (for instance, cast DateTime to DateTime?).
...
How different is Objective-C from C++? [closed]
...Objective-C is a more perfect superset of C. In C and Objective-C implicit casting from void* to a struct pointer is allowed.
Foo* bar = malloc(sizeof(Foo));
C++ will not compile unless the void pointer is explicitly cast:
Foo* bar = (Foo*)malloc(sizeof(Foo));
The relevance of this to every da...
How can I check a C# variable is an empty string “” or null? [duplicate]
...
Are we to assume that this conversion of stringVar to a cast object returns empty string for both null and empty string assigned to the stringVar variable, but converting the same stringVar without the cast returns null and empty string instead? Im just trying to find out all the ...
Convert an enum to List
...T);
return !t.IsEnum ? null : Enum.GetValues(t).Cast<Enum>().Select(x => x.GetDescription()).ToList();
}
When you call this helper you will get the list of item descriptions.
List<string> items = HelperMethods.GetListOfDescription<CancelReasonEnum>();
ADDITION:...
Is there type Long in SQLite?
...tant: retrieve the value from cursor as LONG
Cursor cursor = db.rawQuery("SELECT * FROM " + TABLE_A, null);
long value = cursor.getLong(0);
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What is the proper way to display the full InnerException?
...s()
.Where(e => !String.IsNullOrWhiteSpace(e.Message))
.Select(e => e.Message.Trim());
string flattened = String.Join(Environment.NewLine, messages); // <-- the separator here
return flattened;
}
public static IEnumerable<Exception> GetAllExceptions(this Excep...
How do you implement a class in C? [closed]
...s the proper class, i.e. RectangleClass *. This means you often have to do casts, but they provide handy macros do help with that, so you can always cast BASECLASS *p to SUBCLASS * using just SUBCLASS(p).
– unwind
Sep 10 '09 at 8:03
...
capturing self strongly in this block is likely to lead to a retain cycle
...ple of members of self in this block, most likely just to update a slider. Casting self is overkill. Instead, it's better to be explicit and cast only the objects that you truly need inside the block. For example, if it's an instance of UISlider*, say, _timeSlider, just do the following before the b...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...
Whenever using "%p" on printf, you should cast the pointer to void * as in printf("%p", (void *)str); When printing a size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44...
round() for float in C++
....49999999999999994, (see it live).
Another common implementation involves casting a floating point type to an integral type, which can invoke undefined behavior in the case where the integral part can not be represented in the destination type. We can see this from the draft C++ standard section 4....