大约有 44,000 项符合查询结果（耗时：0.0336秒） [XML]
C# pattern to prevent an event handler hooked twice [duplicate]
...ution and the best one (considering performance) is:
private EventHandler _foo;
public event EventHandler Foo {
add {
_foo -= value;
_foo += value;
}
remove {
_foo -= value;
}
}
No Linq using required. No need to check for null before cancelling a subscrip...
cancelling a handler.postdelayed process
... this to post a delayed runnable:
myHandler.postDelayed(myRunnable, SPLASH_DISPLAY_LENGTH);
And this to remove it: myHandler.removeCallbacks(myRunnable);
share
|
improve this answer
|
...
How to convert a Django QuerySet to a list
...
You could do this:
import itertools
ids = set(existing_answer.answer.id for existing_answer in existing_question_answers)
answers = itertools.ifilter(lambda x: x.id not in ids, answers)
Read when QuerySets are evaluated and note that it is not good to load the whole result int...
Should I use alias or alias_method?
I found a blog post on alias vs. alias_method . As shown in the example given in that blog post, I simply want to alias a method to another within the same class. Which should I use? I always see alias used, but someone told me alias_method is better.
...
jQuery get value of selected radio button
...
Just use.
$('input[name="name_of_your_radiobutton"]:checked').val();
So easy it is.
share
|
improve this answer
|
follow
...
How to print to stderr in Python?
...ound this to be the only one short + flexible + portable + readable:
from __future__ import print_function
import sys
def eprint(*args, **kwargs):
print(*args, file=sys.stderr, **kwargs)
The function eprint can be used in the same way as the standard print function:
>>> print("Test...
Run a Python script from another Python script, passing in arguments [duplicate]
...nction inside script1 directly:
for i in range(whatever):
script1.some_function(i)
If necessary, you can hack sys.argv. There's a neat way of doing this using a context manager to ensure that you don't make any permanent changes.
import contextlib
@contextlib.contextmanager
def redirect_argv...
Doing something before program exit
...int a message when my application was terminating:
import atexit
def exit_handler():
print 'My application is ending!'
atexit.register(exit_handler)
Just be aware that this works great for normal termination of the script, but it won't get called in all cases (e.g. fatal internal errors).
...
Getting a map() to return a list in Python 3.x
...o be ASCII/latin-1 is to do bulk conversions at the C layer: bytes(sequence_of_ints_in_range_0_to_256).decode('latin-1') which makes a str faster by avoiding Python function calls for each element in favor of a bulk conversion of all elements using only C level function calls. You can wrap the above...
How to search a specific value in all tables (PostgreSQL)?
...
How about dumping the contents of the database, then using grep?
$ pg_dump --data-only --inserts -U postgres your-db-name > a.tmp
$ grep United a.tmp
INSERT INTO countries VALUES ('US', 'United States');
INSERT INTO countries VALUES ('GB', 'United Kingdom');
The same utility, pg_dump, can...