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What is a raw type and why shouldn't we use it?
... String name = (String) o;
System.out.println(name);
} // throws ClassCastException!
// java.lang.Boolean cannot be cast to java.lang.String
Now we run into trouble at run-time, because names contains something that isn't an instanceof String.
Presumably, if you want names to contain only...
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 ?? "")....
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...
How can I use PHP to dynamically publish an ical file to be read by Google Calendar?
Any Google search on PHP ical just brings up phpicalendar and how to parse or read IN ical files. I just want to write a PHP file that pulls events from my database and writes them out in ical format.
...
What is the list of valid @SuppressWarnings warning names in Java?
...ngs
boxing to suppress warnings relative to boxing/unboxing operations
cast to suppress warnings relative to cast operations
dep-ann to suppress warnings relative to deprecated annotation
deprecation to suppress warnings relative to deprecation
fallthrough to suppress warnings relative to ...
What are the differences between “generic” types in C++ and Java?
...acro). In Java they are basically syntactic sugar to minimize boilerplate casting of Objects. Here is a pretty decent introduction to C++ templates vs Java generics.
To elaborate on this point: when you use a C++ template, you're basically creating another copy of the code, just as if you used a ...
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 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 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 ...
How do I enumerate through a JObject?
...asons I don't understand, you can't use it with Linq unless you explicitly cast to the enumerable type. I.e. you ((IEnumerable<KeyValuePair<string, JToken>>)obj).Select(...) instead of plain-old obj.Select(...); or at least that's what I found it one part of my code.
...