大约有 16,000 项符合查询结果（耗时：0.0335秒） [XML]
What does “javascript:void(0)” mean?
...
The void operator evaluates the given
expression and then returns undefined.
The void operator is often used merely
to obtain the undefined primitive
value, usually using “void(0)” (which
is equivalent to “void 0”). In these
cases, th...
What's the 'Ruby way' to iterate over two arrays at once
More of a syntax curiosity than a problem to solve...
7 Answers
7
...
Get current batchfile directory
...the path of the caller of the batch, not the batch file location.
You can get the name of the batch script itself as typed by the user with %0 (e.g. scripts\mybatch.bat). Parameter extensions can be applied to this so %~dp0 will return the Drive and Path to the batch script (e.g. W:\scripts\) and %...
Understanding ibeacon distancing
Trying to grasp a basic concept of how distancing with ibeacon (beacon/ Bluetooth-lowenergy/BLE) can work. Is there any true documentation on how far exactly an ibeacon can measure. Lets say I am 300 feet away...is it possible for an ibeacon to detect this?
...
WebRTC - scalable live stream broadcasting / multicasting
PROBLEM:
12 Answers
12
...
What is the difference between is_a and instanceof?
...of PHP 5.3.9, the functionality of is_a() has changed. The original answer below states that is_a() must accept an Object as the first argument, but PHP versions >= 5.3.9 now accept an optional third boolean argument $allow_string (defaults to false) to allow comparisons of string class names ins...
Require returns an empty object
...
This is because you have a circular dependency. Node.js handles this in a very specific way:
The first module loads and runs (in this case, book.js). It (book.js) will load and run the second module (author.js) when it (book.js) re...
Why doesn't Java Map extend Collection?
I was surprised by the fact that Map<?,?> is not a Collection<?> .
9 Answers
...
Why am I getting a “401 Unauthorized” error in Maven?
...so get an error (and off the top of my head is also a 401) if you try to publish something to a releases repository and that version already exists in the repository. So you might find that by publishing from the command line it works, but then when you do it from a script it fails (because it didn...
How do ACID and database transactions work?
...
ACID is a set of properties that you would like to apply when modifying a database.
Atomicity
Consistency
Isolation
Durability
A transaction is a set of related changes which is used to achieve some of the ACID properties. Transactions are tools to achieve the ACID properties.
Atomicity me...