大约有 47,000 项符合查询结果（耗时：0.0530秒） [XML]
Converting a double to an int in C#
...t.ToInt32 will throw an exception. Cast will return an int, but you won'y know which one (in my implementation it's Int32.MinValue) because you're in unchecked context. (Should you be in checked context, the cast will throw an exception as well in these cases.)
– Jeppe Stig Nie...
How do I use variables in Oracle SQL Developer?
...
Ok I know this a bit of a hack but this is a way to use a variable in a simple query, not a script:
WITH
emplVar AS
(SELECT 1234 AS id FROM dual)
SELECT
*
FROM
employees,
emplVar
WHERE
EmployId=emplVar.id;
...
Getting the last element of a list
...st get the last element,
without modifying the list, and
assuming you know the list has a last element (i.e. it is nonempty)
pass -1 to the subscript notation:
>>> a_list = ['zero', 'one', 'two', 'three']
>>> a_list[-1]
'three'
Explanation
Indexes and slices can take neg...
Array versus List: When to use which?
...e you want to add/remove data, since resizing arrays is expensive. If you know the data is fixed length, and you want to micro-optimise for some very specific reason (after benchmarking), then an array may be useful.
List<T> offers a lot more functionality than an array (although LINQ evens i...
How to open a second activity on click of button in android app
...
@HenryAspden i have edit my code now try this. i have put this code in onCreate try this way.
– J.D.
Nov 2 '12 at 12:15
...
How can I fill a div with an image while keeping it proportional?
...
An old question but deserves an update as now there is a way.
The correct CSS based answer is to use object-fit: cover, which works like background-size: cover. Positioning would be taken care of by object-position attribute, which defaults to centering.
But there ...
Does ARC support dispatch queues?
...he short answer: YES, ARC retains and releases dispatch queues.
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage them.
If your deployment target is iOS 6...
How can I launch multiple instances of MonoDevelop on the Mac?
... Update to the checkbox label in case someone find this, it now says "Close current workspace"
– Tiago
Feb 23 '12 at 14:20
...
if A vs if A is not None:
...
@cedbeu, Seems to depend on the value of A. I tested now python -m timeit -s"a=0" "if a: pass" "else: pass" is faster than python -m timeit -s"a=0" "if a is None: pass" "else: pass" but python -m timeit -s"a=1" "if a: pass" "else: pass" is slower. Might be platform dependant, s...
Is the buildSessionFactory() Configuration method deprecated in Hibernate
... using StandardServiceRegistryBuilder instead. So I guess the call should now be new StandardRegistryBuilder().applySettings(configuration.getProperties()).build();
– Simon B
Jan 21 '14 at 8:31
...