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How to check whether an array is empty using PHP?
... is empty.
}
If you need to clean out empty values before checking (generally done to prevent explodeing weird strings):
foreach ($playerlist as $key => $value) {
if (empty($value)) {
unset($playerlist[$key]);
}
}
if (empty($playerlist)) {
//empty array
}
...
PHP parse/syntax errors; and how to solve them
...as T_STRING explains which symbol the parser/tokenizer couldn't process finally. This isn't necessarily the cause of the syntax mistake, however.
It's important to look into previous code lines as well. Often syntax errors are just mishaps that happened earlier. The error line number is just where ...
HTTP authentication logout via PHP
...ecification (section 15.6):
Existing HTTP clients and user agents typically retain authentication
information indefinitely. HTTP/1.1. does not provide a method for a
server to direct clients to discard these cached credentials.
On the other hand, section 10.4.2 says:
If the request...
在线服务的黑天鹅 - 资讯 - 清泛网 - 专注C/C++及内核技术
...利用周日休息一下，但是一醒来就收到消息说某服务有些问题。于是赶紧连线了一堆正在处理事件的工程师，等拿到初步的原因分析之后，已经4小时之后了。
“墨菲定律”，一位工程师说，“前几天觉得这个地方有些隐患，已...
Difference between \w and \b regular expression meta characters
...chor like the caret and the dollar sign. It matches at a position that is called a "word boundary". This match is zero-length.
There are three different positions that qualify as word boundaries:
Before the first character in the string, if the first character is
a word character.
After the last ...
Do I have to guard against SQL injection if I used a dropdown?
... make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to sav...
What are five things you hate about your favorite language? [closed]
...ld be matched to another NULL value. If you understand this (what also is called ternary logic) than you might understand the reason for introducing the "IS" operator for testing against NULL.
– Alex
Aug 26 '10 at 16:58
...
How to get a substring between two strings in PHP?
...ieves that. I do not want to think about regex (well, I could do one but really don't think it's the best way to go). Thinking of strpos and substr functions.
Here's an example:
...
How to loop through an associative array and get the key? [duplicate]
... using PHP 5, you should avoid using foreach by reference values and since all foreaches use internal array pointer ( current($Array) ) nesting foreaches or using PHP array functions can do weird things.
– Chaoix
Jul 12 '19 at 15:13
...
怎么解决MQTT连接掉线，自动连接问题，同时解决，反复断开连接，断开连接问...
解决MQTT退出后台后掉线自动连接问题，现在可以实现自动连接，但是在返回控制界面的时候，反复断开反复链接，还有切换页面的时候返回也是同样的问题，还有连接一个服务器，需要每个页面单独设置MQTT连接吗，是不是可以...