大约有 40,000 项符合查询结果（耗时：0.0404秒） [XML]
ARC and bridged cast
...__bridge_transfer? Otherwise it would seem that the moment CFRelease() is called the object is gone and points to nothing. Similarly, when you use __bridge_retain, does ARC reduce the op's retain count by 1? Else it seems that the object would never be properly released.
– Tony...
Convert a row of a data frame to vector
...
Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Bring element to front using CSS
...
I don't really remember the circumstances of my question clearly, but my problem was, that I understood what z-index does, but still it did not work. What I have learned from this answer is, that with z-index you have to take into cons...
How to convert An NSInteger to an int?
... front of the NSInteger? For example, (int)myInteger whenever you want to call the integer form, so that you do not have to create a new variable.
– chandhooguy
Dec 28 '14 at 22:05
...
Super-simple example of C# observer/observable with delegates
...
The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
How to get current timestamp in milliseconds since 1970 just the way Java gets
...e UNIX epoch, but the spec only says it must be the system-wide real time wall clock. There is no requirement for the steady_clock to match reality, only that it only move forward.
– Oz.
Jul 27 '15 at 23:22
...
Get operating system info
...x]{2})', 'Windows');
// Doesn't seem like these are necessary...not totally sure though..
//$ros[] = array('(winnt)([0-9]{1,2}\.[0-9]{1,2}){0,1}', 'Windows NT');
//$ros[] = array('(windows nt)(([0-9]{1,2}\.[0-9]{1,2}){0,1})', 'Windows NT'); // fix by bg
$ros[] = array('Windows ME', '...
__getattr__ on a module
...
A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__...
How to read keyboard-input?
... mixing different Pythons here (Python 2.x vs. Python 3.x)...
This is basically correct:
nb = input('Choose a number: ')
The problem is that it is only supported in Python 3. As @sharpner answered, for older versions of Python (2.x), you have to use the function raw_input:
nb = raw_input('Choose...
How to import the class within the same directory or sub directory?
I have a directory that stores all the .py files.
13 Answers
13
...