大约有 47,000 项符合查询结果（耗时：0.0730秒） [XML]
PostgreSQL - Rename database
...think it's better to keep table names restricted to just lowercase letters and underscore if possible!
– Aswin Sanakan
Feb 17 at 6:52
...
Why does substring slicing with index out of range work?
...
You're correct! 'example'[3:4] and 'example'[3] are fundamentally different, and slicing outside the bounds of a sequence (at least for built-ins) doesn't cause an error.
It might be surprising at first, but it makes sense when you think about it. Indexi...
Salting Your Password: Best Practices?
...
Prefix or suffix is irrelevant, it's only about adding some entropy and length to the password.
You should consider those three things:
The salt has to be different for every password you store. (This is quite a common misunderstanding.)
Use a cryptographically secure random number generat...
Using the “final” modifier whenever applicable in Java [closed]
...eywords in your code, but pretty soon you'll stop noticing the word itself and will simply think, that-thing-will-never-change-from-this-point-on (you can take it from me ;-)
I think it's good practice. I am not using it all the time, but when I can and it makes sense to label something final I'll ...
How do I concatenate const/literal strings in C?
I'm working in C, and I have to concatenate a few things.
17 Answers
17
...
Python - abs vs fabs
...n (if it can't, it throws an exception). It then takes the absolute value, and returns the result as a float.
In addition to floats, abs() also works with integers and complex numbers. Its return type depends on the type of its argument.
In [7]: type(abs(-2))
Out[7]: int
In [8]: type(abs(-2.0))
Out...
'UserControl' constructor with parameters in C#
...'t need to track down a bunch of data, it can immediately create something and just see it with sensible (if uninteresting) results.
Ease of use for the designer. Designer code is clearer and easier to parse in general.
Discourages unusual data dependencies within a single component. (Though even ...
How can I validate a string to only allow alphanumeric characters in it?
...n use LINQ:
if (yourText.All(char.IsLetterOrDigit))
{
//just letters and digits.
}
yourText.All will stop execute and return false the first time char.IsLetterOrDigit reports false since the contract of All cannot be fulfilled then.
Note! this answer do not strictly check alphanumerics (whi...
How do I remove leading whitespace in Python?
...
The lstrip() method will remove leading whitespaces, newline and tab characters on a string beginning:
>>> ' hello world!'.lstrip()
'hello world!'
Edit
As balpha pointed out in the comments, in order to remove only spaces from the beginning of the string, lstrip(' ') s...
Is there still any reason to learn AWK?
...you move to more exotic systems, knowing a little awk is going to be Real Handy.
awk can also be used for more than just text processing. For example one of my supervisors writes astronomy code in awk - that is how utterly old school and awesome he is. Back in his days, it was the best tool for the...