大约有 36,010 项符合查询结果（耗时：0.0426秒） [XML]
Null check in an enhanced for loop
...se an empty list won't fail.
If you get this list from somewhere else and don't know if it is ok or not you could create a utility method and use it like this:
for( Object o : safe( list ) ) {
// do whatever
}
And of course safe would be:
public static List safe( List other ) {
return ...
What is a smart pointer and when should I use one?
...nership.
// p1 gets set to empty!
p2->DoSomething(); // Works.
p1->DoSomething(); // Oh oh. Hopefully raises some NULL pointer exception.
OLD ANSWER
A smart pointer is a class that wraps a 'raw' (or 'bare') C++ pointer, to manage the lifetime of the objec...
Cannot read configuration file due to insufficient permissions
...as above, but a little longer and simpler and improved.
First of all: you don't have to change anything in your config file. It's OK. The problem is with windows file permissions.
This problems occurs because your application can not access and read web.config file.
Make the file accessible to II...
C++ catching all exceptions
...d design. You can use c++11's new current_exception mechanism, but if you don't have the ability to use c++11 (legacy code systems requiring a rewrite), then you have no named exception pointer to use to get a message or name. You may want to add separate catch clauses for the various exceptions ...
How do I format a date with Dart?
...an instance of DateTime and I would like to format that to a String. How do I do that? I want to turn the date into a string, something like "2013-04-20".
...
How do I remove background-image in css?
... gives all DIVs a background image.
I have one div (with id='a') which I don't want it to have the background image.
What css rule do I have to give it?
...
Should I use Vagrant or Docker for creating an isolated environment? [closed]
...
If your purpose is the isolation, I think Docker is what you want.
Vagrant is a virtual machine manager. It allows you to script the virtual machine configuration as well as the provisioning. However, it is still a virtual machine depending on VirtualBox (or others)...
std::string formatting like sprintf
...ormat std::string with sprintf and send it into file stream. How can I do this?
40 Answers
...
How to have conditional elements and keep DRY with Facebook React's JSX?
How do I optionally include an element in JSX? Here is an example using a banner that should be in the component if it has been passed in. What I want to avoid is having to duplicate HTML tags in the if statement.
...
What's the cleanest way of applying map() to a dictionary in Swift?
... 14 '14 at 10:40
Brent Royal-GordonBrent Royal-Gordon
15.9k55 gold badges5151 silver badges8686 bronze badges
...