大约有 45,000 项符合查询结果（耗时：0.0706秒） [XML]
No ConcurrentList in .Net 4.0?
...
And if you need something similar to List<T> that uses old-skool, monitor-based synchronisation, there's SynchronizedCollection<T> hidden away in the BCL: msdn.microsoft.com/en-us/library/ms668265.aspx
...
How do I install Maven with Yum?
...-maven/epel-apache-maven.repo -O /etc/yum.repos.d/epel-apache-maven.repo
Now you can install maven like this:
yum install apache-maven
Once done, maven 3 will be installed and mvn -version will show you which version you've got - I had 3.2.1.
This worked perfectly for me on CentOS 6 with one e...
JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
a "problem" which i have every now and then is that i have an object e.g. user = {} and through the course of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
...
Get the client IP address using PHP [duplicate]
... to get the IP address.
The below both functions are equivalent with the difference only in how and from where the values are retrieved.
getenv() is used to get the value of an environment variable in PHP.
// Function to get the client IP address
function get_client_ip() {
$ipaddress = '';
...
How to ignore deprecation warnings in Python
...gs("ignore",category=DeprecationWarning)
import md5, sha
yourcode()
Now you still get all the other DeprecationWarnings, but not the ones caused by:
import md5, sha
share
|
improve this ans...
How to check if command line tools is installed
I have a macbook pro with OS X 10.8.2.
XCode is installed. I know this as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is ...
How is “int* ptr = int()” value initialization not illegal?
...
@NeilG: This stays the same in C++11, though there is now also a nullptr, which you can use instead of 0 or NULL in new code.
– Jerry Coffin
Nov 9 '11 at 23:02
...
How to check if an object is a list or tuple (but not string)?
...an be treated as a list. So, don't check for the type of a list, just see if it acts like a list.
But strings act like a list too, and often that is not what we want. There are times when it is even a problem! So, check explicitly for a string, but then use duck typing.
Here is a function I wro...
Null vs. False vs. 0 in PHP
...s.
0 is an int. Nothing to do with the rest above, used for mathematics.
Now, what is tricky, it's that in dynamic languages like PHP, all of them have a value in a boolean context, which (in PHP) is False.
If you test it with ==, it's testing the boolean value, so you will get equality. If you t...
What is the correct way of using C++11's range-based for?
...
The above code prints the elements (ints) in the vector:
1 3 5 7 9
Now consider another case, in which the vector elements are not just simple integers,
but instances of a more complex class, with custom copy constructor, etc.
// A sample test class, with custom copy semantics.
class X
{
pu...