大约有 40,000 项符合查询结果（耗时：0.0567秒） [XML]
Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
Making a WinForms TextBox behave like your browser's address bar
...
First of all, thanks for answers! 9 total answers. Thank you.
Bad news: all of the answers had some quirks or didn't work quite right (or at all). I've added a comment to each of your posts.
Good news: I've found a way to make it wo...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...
If the script is the same across all users, you can use a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the....
Autoreload of modules in IPython [duplicate]
Is there a way to have IPython automatically reload all changed code? Either before each line is executed in the shell or failing that when it is specifically requested to. I'm doing a lot of exploratory programming using IPython and SciPy and it's quite a pain to have to manually reload each module...
How do I catch a PHP fatal (`E_ERROR`) error?
... because processing should not typically be recovered after a fatal error. String matching an output buffer (as suggested by the original post the technique described on PHP.net) is definitely ill-advised. It's simply unreliable.
Calling the mail() function from within an error handler method prove...
jQuery Validate Plugin - Trigger validation of single field
I've got a form that can optionally be pre-populated via facebook connect. Once a user connects, their name and email are automatically filled in. The problem is that this doesn't trigger the remote validation to check if the email already exists.
...
How to pull a random record using Django's ORM?
...['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
share
|
improve this answer
|
follow
|
...
Specifying rails version to use when creating a new application
I have two versions of rails (2.1.0 and 2.2.2) installed in my computer.
7 Answers
7
...
Get IP address of visitors using Flask for Python
...emote_addr)
When proxies, such as nginx, forward addresses, they typically include the original IP somewhere in the request headers.
Update See the flask-security implementation. Again, review the documentation about ProxyFix before implementing. Your solution may vary based on your particular...
package R does not exist
...a code auto-generated from your XML files (UI layout, internationalization strings, etc.) If the code used to be working before (as it seems it is), you need to tell your IDE to regenerate these files somehow:
in IntelliJ, select Tools > Android > Generate sources for <project>
(If you...