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php：获取数组第一个值 - 更多技术 - 清泛网 - 专注C/C++及内核技术
php：获取数组第一个值自PHP 5.4版本后可以使用[ ]来取数据指定位置的元素，索引从0开始，即$arr[0]取数组第一个值。不过为了兼容性，建议还是采取reset(),current(),next()等函数来取数组中的值，reset($arr)后current($arr)取第一个值。自...
PHP优化杂烩 - 更多技术 - 清泛网 - 专注C/C++及内核技术
PHP优化杂烩讲 PHP 优化的文章往往都是教大家如何编写高效的代码，本文打算从另一个角度来讨论问题，教大家如何配置高效的环境，如此同样能够达到优...讲 PHP 优化的文章往往都是教大家如何编写高效的代码，本文打算从另...
LINUX下用PHPIZE安装PHP GD扩展 - PHP - 清泛IT论坛，有思想、有深度
...zqp2013 于 2015-4-26 14:39 编辑
环境：LNMP in centOS 6.4。linux下PHP的扩展可以用phpize的方法，比较简单地进行启用。以下以PHP-GD2 库安装为例子。sudo yum install php-gd2 png jpeg freetype //YUM安装扩展cd /app/php-5.4.13/ext/gd &nbs...
Laravel Check If Related Model Exists
...hp 7.2+ you can't use count on the relation object, so there's no one-fits-all method for all relations. Use query method instead as @tremby provided below:
$model->relation()->exists()
generic solution working on all the relation types (pre php 7.2):
if (count($model->relation))
{
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@ character before a function call
What is the difference between these two function calls in PHP?
5 Answers
5
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Increasing the maximum number of TCP/IP connections in Linux
...local_port_range = 32768 61000
net.ipv4.tcp_fin_timeout = 60
This basically means your system cannot consistently guarantee more than (61000 - 32768) / 60 = 470 sockets per second. If you are not happy with that, you could begin with increasing the port_range. Setting the range to 15000 61000 is...
PHP namespaces and “use”
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So if i create another file called bootstrap.php and place an autoloader inside along with $circle = new Circle(); It includes the Circle.php but I am getting an error: Fatal error: Class 'Shape' not found in .../Circle.php on line 6. It appears to load Circle.php but n...
How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what'...
Add number of days to a date
... about taking their date calculations seriously - its easy to forgot about all of the exceptions.
– JJ Rohrer
Jul 24 '14 at 18:28
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String concatenation vs. string substitution in Python
...catenation is (significantly) faster according to my machine. But stylistically, I'm willing to pay the price of substitution if performance is not critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating.
>>&g...