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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...
How to convert An NSInteger to an int?
...
I get a warning using the suggested "casting": Implicit conversion loses integer precision: 'NSUInteger' (aka 'unsigned long') to 'int'
– djcj
Sep 18 '14 at 16:52
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How to determine an object's class?
... are still more methods: Class.isAssignableFrom() and simply attempting to cast the object (which might throw a ClassCastException).
Possible ways summarized
Let's summarize the possible ways to test if an object obj is an instance of type C:
// Method #1
if (obj instanceof C)
;
// Method #2...
Why does Convert.ToString(null) return a different value if you cast null?
...2f10355736%2fwhy-does-convert-tostringnull-return-a-different-value-if-you-cast-null%23new-answer', 'question_page');
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What are POD types in C++?
...en pointers to vtables, offsets that get applied to the address when it is cast to other types (at least if the target's POD too), constructors, or destructors. Roughly speaking, a type is a POD when the only things in it are built-in types and combinations of them. The result is something that "act...
printf format specifiers for uint32_t and size_t
...eded is that the format specifiers and the types agree, and you can always cast to make that true. long is at least 32bits, so %lu together with (unsigned long)k is always correct. size_t is trickier, which is why %zu was added in C99. If you can't use that, then treat it just like k (long is the bi...
Passing data between a fragment and its container activity
...ithin YOUR Activity (and not the parent Android activity) you will need to cast your getActivity() call: ((MyActivity) getActivity()).getResult();
– Nick
Feb 21 '12 at 17:20
...
How to pass values between Fragments
... I tried step 5, That i'm calling listactivity from fragment and after selecting item from that activity, i want to come back in fragment with selected file name. But its not working, its giving me Nullpointer Exception at onCreateView. Any solution on this please? This is my question stackoverf...
How to do ToString for a possibly null object?
...
C# 6.0 Edit:
With C# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "")....
Why is null an object and what's the difference between null and undefined?
...ceptually, the same as false or "" or such, even if they equate after type casting, i.e.
name = false;
You: What is name?
JavaScript: Boolean false.
name = '';
You: What is name?
JavaScript: Empty string
*: name in this context is meant as a variable which has never been defined. It could be any ...