What does "++" mean in PHP?

Possible Duplicate: Reference - What does this symbol mean in PHP? I've been learning PHP by reading all sorts of things on the web. I've trying to figure out what this is called so I can look it up and read about it and learn how it works. It's the "++" in the code I'm assuming counts up so that the codes knows when to do a new line. I not looking for corrections

“++”在PHP中意味着什么?

可能重复: 参考 - 这个符号在PHP中的含义是什么? 我一直在通过阅读网络上的各种东西来学习PHP。 我试图弄清楚这是叫什么,所以我可以查看它并阅读它并了解它是如何工作的。 这是我假设计数的代码中的“++”,以便代码知道何时执行新的操作。 我不在寻找更正此代码我正在寻找什么叫“++”,所以我可以查找它。 $i = 0 if (++$i == 10) { echo "new line"; } 它被称为前缀增量一元运算符 。 它递增数字或字符,然后返

PHP array delete by value (not key)

I have a PHP array as follows: $messages = [312, 401, 1599, 3, ...]; I want to delete the element containing the value $del_val (for example, $del_val=401 ), but I don't know its key. This might help: each value can only be there once . I'm looking for the simplest function to perform this task please. Using array_search() and unset , try the following: if (($key = array_search($d

按数值删除PHP数组(不是键)

我有一个PHP数组,如下所示: $messages = [312, 401, 1599, 3, ...]; 我想删除包含值$del_val的元素(例如$del_val=401 ),但我不知道它的关键。 这可能有所帮助: 每个值只能出现一次 。 我正在寻找最简单的功能来执行此任务。 使用array_search()并unset ,请尝试以下操作: if (($key = array_search($del_val, $messages)) !== false) { unset($messages[$key]); } array_search()返回它找到的元素的键,它可

What is the difference between single

I'm not an expert in PHP programming, but I'm a little confused why I see some code in PHP with string placed in single quotes and sometimes in double quotes. I just know in .NET, or the C language, if it is in single quote, that means it is a character, not a string. PHP strings can be specified not just in two ways, but in four ways. Single quoted strings will display things almos

单身之间有什么区别

我不是PHP编程的专家,但我有点困惑,为什么我在PHP中看到一些代码,字符串放在单引号中,有时用双引号。 我只是在.NET或C语言中知道它是否在单引号中,这意味着它是一个字符,而不是一个字符串。 不仅可以用两种方式指定PHP字符串 ,但有四种方式。 单引号字符串将几乎完全“按原样”显示。 变量和大多数转义序列不会被解释。 例外是显示一个文字单引号,你可以使用反斜杠'来转义它,并且显示一个反斜杠,你可以用另

Is there a function to make a copy of a PHP array to another?

Is there a function to make a copy of a PHP array to another? I have been burned a few times trying to copy PHP arrays. I want to copy an array defined inside an object to a global outside it. In PHP arrays are assigned by copy, while objects are assigned by reference. This means that: $a = array(); $b = $a; $b['foo'] = 42; var_dump($a); Will yield: array(0) { } Whereas: $a = new StdCl

有没有一个函数可以将PHP数组的副本拷贝到另一个?

有没有一个函数可以将PHP数组的副本拷贝到另一个? 我已经烧了几次试图复制PHP数组。 我想将一个对象中定义的数组复制到它外面的一个全局对象中。 在PHP中,数组通过复制进行分配,而对象则通过引用进行分配。 这意味着: $a = array(); $b = $a; $b['foo'] = 42; var_dump($a); 会产生: array(0) { } 鉴于: $a = new StdClass(); $b = $a; $b->foo = 42; var_dump($a); 产量: object(stdClass)#1 (1) { ["f

What is stdClass in PHP?

请定义stdClass是什么。 stdClass is PHP's generic empty class, kind of like Object in Java or object in Python ( Edit: but not actually used as universal base class; thanks @Ciaran for pointing this out). It is useful for anonymous objects, dynamic properties, etc. An easy way to consider the StdClass is as an alternative to associative array. See this example below that shows how json_de

什么是PHP中的stdClass?

请定义stdClass是什么。 stdClass是PHP的通用空类,有点像Java中的Object或Python中的object ( 编辑:但实际上并未用作通用基类;感谢@Ciaran指出了这一点)。 这对匿名对象,动态属性等非常有用。 考虑StdClass的简单方法是作为关联数组的替代方法。 看下面的这个例子显示了json_decode()如何获得一个StdClass实例或一个关联数组。 在这个例子中也没有显示, SoapClient::__soapCall返回一个StdClass实例。 <?php //Ex

What are the differences in die() and exit() in PHP?

What are the differences between die() and exit() functions in PHP ? I think both have the same functionality, but I doubt there is something different in both... what is it? There's no difference - they are the same. PHP Manual for exit : Note: This language construct is equivalent to die() . PHP Manual for die : This language construct is equivalent to exit() . DIFFERENCE IN O

PHP中die()和exit()有什么区别?

PHP die()和exit()函数有什么区别? 我认为两者都具有相同的功能,但我怀疑两者有什么不同......它是什么? 没有区别 - 它们是一样的。 PHP手册exit : 注意:这种语言结构等同于die() 。 die PHP手册: 这个语言结构等同于exit() 。 原产地的差异 die()和exit()在PHP中的区别在于它们的起源 。 exit()来自C中的 exit() 。 die()来自Perl中的 die 。 功能等同 die()和exit()是等价的函数。 PHP手册

How to calculate the difference between two dates using PHP?

I have two dates of the form: Start Date: 2007-03-24 End Date: 2009-06-26 Now I need to find the difference between these two in the following form: 2 years, 3 months and 2 days How can I do this in PHP? The best course of action is using PHP's DateTime (and DateInterval ) objects. Each date is encapsulated in a DateTime object, and then a difference between the two can be made: $fir

如何计算使用PHP的两个日期之间的差异?

我有两种形式的日期: Start Date: 2007-03-24 End Date: 2009-06-26 现在我需要通过以下形式找出这两者之间的区别: 2 years, 3 months and 2 days 我怎样才能在PHP中做到这一点? 最好的做法是使用PHP的DateTime (和DateInterval )对象。 每个日期都封装在一个DateTime对象中,然后可以做出两者的区别: $first_date = new DateTime("2012-11-30 17:03:30"); $second_date = new DateTime("2012-12-21 00:00:00");

Understanding PHP & (ampersand, bitwise and) operator

Two operations which are fundamental to binary systems are OR and AND. OR means 'if either A is on or B is on'. A real world example would be two switches in parallel. If either is allowing current through, then current passes through. AND means 'if both A and B is on'. The real world example is two switches in series. Current will only pass through if both are allowing cu

了解PHP&(&符号,按位和)运算符

对于二进制系统来说两个基本的操作是OR和AND。 OR意思是'如果A打开或B打开'。 一个真实世界的例子是两个并联的开关。 如果任一个允许电流通过,则电流通过。 AND表示'如果A和B都打开'。 真实世界的例子是两个串联的开关。 如果两者都允许电流通过,电流只能通过。 在计算机中,这些不是物理交换机,而是半导体,其功能称为逻辑门。 他们和开关做类似的事情 - 对电流或电流做出反应。 当应用于整数

Understanding PHP & (ampersand, bitwise and) operator

& is binary and . If you have a binary value, and you and with another binary value, then the result will be the bitwise and of the two. An example: 01101010 & 01011001 = 01001000 The rightmost bit is either a 1 (and in that case the number is an odd number) or it is a 0, in which case the number is even. If you & a number with 1, you only look at the least significant bit, and

了解PHP&(&符号,按位和)运算符

&是二进制and 。 如果你有一个二进制值,你and另一个二进制值,那么结果将是按位and两个。 一个例子: 01101010 & 01011001 = 01001000 最右边的位是1(在这种情况下,数字是奇数),或者是0,在这种情况下,数字是偶数。 如果您& 1的数字,你只能看至少显著位,而如果检查的数量是1或0正如其他人所说,看位运算符的信息他们是如何工作的。 对于二进制系统来说两个基本的操作是OR和AND。 OR意思是'如果A

Get absolute path of current script

I have searched high and low and get a lot of different solutions and varialbles containing info to get the absolute path. But they seem to work under some conditions and not under others. Is there one silver bullet way to get the absolute path to the current executing script in php? For me the script will be running from the command line but it should just as well function if run within apach

获取当前脚本的绝对路径

我搜索了高和低,并获得了许多不同的解决方案和包含信息的变量来获取绝对路径。 但他们似乎在某些条件下工作,而不是在其他条件下工作。 有没有一种银子弹的方式来获取当前执行脚本在PHP中的绝对路径? 对我来说,脚本将从命令行运行,但如果在Apache等内运行,它也应该是一样的功能。 澄清:最初执行的脚本,而不是我们目前所在的文件 __FILE__常量会为您提供当前文件的绝对路径。 UPD : 一旦问题被改为检索开始运