大约有 40,000 项符合查询结果（耗时：0.0481秒） [XML]
How does Django's Meta class work?
I am using Django which allows people to add extra parameters to a class by using class Meta .
6 Answers
...
Thread vs ThreadPool
...rom the pool rather than one I've explicitly created? I'm thinking specifically of .NET here, but general examples are fine.
...
Importing a CSV file into a sqlite3 database table using Python
...lumn headers in the csv file. And close the connection to the database by calling con.close() at the end.
– Jonas
Aug 8 '16 at 21:31
1
...
How to write very long string that conforms with PEP8 and prevent E501
...
Implicit concatenation might be the cleanest solution:
s = "this is my really, really, really, really, really, really," \
" really long string that I'd like to shorten."
Edit On reflection I agree that Todd's suggestion to use brackets rather than line continuation is better for all the reas...
How to resize superview to fit all subviews with autolayout?
...n a UITableViewCell (to determine row height for example) then you should call it against your cell contentView and grab the height.
Further considerations exist if you have one or more UILabel's in your view that are multiline. For these it is imperitive that the preferredMaxLayoutWidth propert...
Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...
Guesswork (even educated guesswork) is fun but you really need to go to the standards documents to be sure. For example, ISO C11 states (my emphasis):
If the value of argc is greater than zero, the string pointed to by argv[0] represents the program name; argv[0][0] shall b...
Are non-synchronised static methods thread safe if they don't modify static class variables?
... case) are also thread-safe because once created they can't be changed and all threads see the same value. On the other hand if the method was accepting (mutable) Date you could have had a problem. Two threads can simultaneously modify that same object instance, causing race conditions and visibilit...
List all sequences in a Postgres db 8.1 with SQL
...
The following query gives names of all sequences.
SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the ...
How to retrieve a module's path?
...
import a_module
print(a_module.__file__)
Will actually give you the path to the .pyc file that was loaded, at least on Mac OS X. So I guess you can do:
import os
path = os.path.abspath(a_module.__file__)
You can also try:
path = os.path.dirname(a_module.__file__)
To ge...
In git, is there a way to show untracked stashed files without applying the stash?
...an stash untracked files. However, said untracked files don't show up at all with git stash show stash@{0} . Is there any way to show untracked stashed files without applying the stash?
...