大约有 40,000 项符合查询结果（耗时：0.0244秒） [XML]
App Inventor 2开发计步器与定位器 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
...能。
2.主题：编写“健身宝”手机应用程序
3.问题：
（1）如何获取走路步数、距离？
（2）如何计算走路时间？
（3）如何获得当前位置？
（4）如何存储信息？
4.规划：
（1）利用pedome...
How to change the session timeout in PHP?
...cted immediately but only whenever the session GC kicks in.
GC is a potentially expensive process, so typically the probability is rather small or even zero (a website getting huge numbers of hits will probably forgo probabilistic GC entirely and schedule it to happen in the background every X minut...
Preferred method to store PHP arrays (json_encode vs serialize)
...ciative array of data in a flat file for caching purposes. I might occasionally come across the need to convert it to JSON for use in my web app but the vast majority of the time I will be using the array directly in PHP.
...
PHP - how to best determine if the current invocation is from CLI or web server?
...
A small caveat about this method: it will not return "cli" when run from a cron job. There's a number od differents keys to choose from inside of $_SERVER to determine more reliably whether the request came via HTTP or not.
...
What's the use of ob_start() in php?
...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet."
For example:
ob_start();
echo("Hello there!"); //would normally get printed to the screen/output to browser
$output = ob_get_contents();
ob_end_clean();
There a...
urlencode vs rawurlencode?
...php.net/manual/en/function.rawurlencode.php)
Returns a string in which all non-alphanumeric characters except -_.~ have been replaced with a percent (%) sign followed by two hex digits. This is the encoding described in » RFC 3986 for protecting literal characters from being interpreted as spec...
How can I add additional PHP versions to MAMP
...
Found a quick fix in the MAMP forums.
Basically it seems MAMP is only allowing 2 versions of PHP to show up. Quick fix, rename the folders you're not bothered about using, for me this meant adding an "X" to my /Applications/MAMP/bin/php/php5.4.10_X folder. Now 5.2.17 ...
搭建高可用mongodb集群（一）——配置mongodb - 大数据 & AI - 清泛网 - 专...
...储、高可扩展性和高可用性这些难题。不过就是因为这些问题Nosql诞生了。
NOSQL有这些优势：
大数据量，可以通过廉价服务器存储大量的数据，轻松摆脱传统mysql单表存储量级限制。
高扩展性，Nosql去掉了关系数据库的关系型...
Using braces with dynamic variable names in PHP
I'm trying to use dynamic variable names (I'm not sure what they're actually called) But pretty much like this:
8 Answers
...
How can I get the MAC and the IP address of a connected client in PHP?
... address, you could parse the output of netstat -ie in Linux, or ipconfig /all in Windows.
Client IP address
You can get the client IP from $_SERVER['REMOTE_ADDR']
Client MAC address
The client MAC address will not be available to you except in one special circumstance: if the client is on the s...