Meaning of "Can't use method return value in write context"

Possible Duplicate: Can't use method return value in write context I sometimes encountered this error Can't use method return value in write context . However, I don't know what does WRITE CONTEXT means in this sentence. Could someone tell me a little general explaination of it. Thank you. The code for this error if you want to refer to is on line if(empty($this->loadUser

“在写入上下文中不能使用方法返回值”的含义

可能重复: 在写入上下文中不能使用方法返回值 我有时遇到此错误Can't use method return value in write context 。 但是,我不知道WRITE CONTEXT在这句话中意味着什么。 有人能告诉我一个一般的解释。 谢谢。 如果你想引用这个错误的代码是在线if(empty($this->loadUser()))然而,只是为了澄清,我只想找出“写上下文”的含义: public function verify() { if(empty($this->loadUser())) $this

Incorrect information in file: './database

I'm completely lost as to how or why this error is displaying when I go to browse the table data. The one thing I did notice was that the Storage Engine has been switched to MyISAM with InnoDB saying it has been disabled. I'm waiting to hear back from the hosting company but is there something I can explore until I hear back from them? The sql should have been backed up on the serve

文件中的信息不正确:'./database

当我去浏览表格数据时,我完全失去了这个错误显示的方式或原因。 我注意到的一件事是,存储引擎已被切换到MyISAM与InnoDB称它已被禁用。 我在等待收到托管公司的回复,但有什么我可以探索,直到我从他们那里听到回来? sql应该已经备份在服务器上,但是当我下载它时,该文件是空的。 非常感谢访问这些数据的任何提示。 听起来你的主机可能已经禁用InnoDB,这将使任何现有的InnoDB表不可用。 他们也可能意外地销毁了In

'HTML Forms' example usage of logical XOR and bit

I am currently teaching a PHP introductory course to students with some background in HTML, CSS and (very basic/limited) JS. While going over the list of various operators in PHP, I was able to give examples for logical AND and OR in context of processing registration forms: AND: We want our users to be above a certain age limit AND accept our terms and conditions. OR: We want new users to p

'HTML Forms'逻辑XOR和位的示例用法

我目前正在为有HTML,CSS和(非常基本/有限)JS背景的学生讲授一门PHP入门课程。 在查看PHP中各种运算符的列表时,我能够在处理注册表单的情况下给出逻辑AND和OR的示例: AND:我们希望我们的用户超过某个年龄限制并接受我们的条款和条件。 或者:我们希望新用户支付注册费,或者提请其他三人注册。 尽管您可以将我的OR示例构建为实际上的XOR。 我正在寻找一个更好的例子,最好是在(类似注册)表单的情况下。 使用Goo

Get first n characters of a string

How can I get the first n characters of a string in PHP? What's the fastest way to trim a string to a specific number of characters, and append '...' if needed? //The simple version for 10 Characters from the beginning of the string $string = substr($string,0,10).'...'; Update: Based on suggestion for checking length (and also ensuring similar lengths on trimmed and untrimmed str

获取字符串的前n个字符

我如何在PHP中获取字符串的前n个字符? 将字符串修剪为特定数量的字符的最快方法是什么,并在需要时追加'...'? //The simple version for 10 Characters from the beginning of the string $string = substr($string,0,10).'...'; 更新: 基于检查长度的建议(以及确保修剪和未修剪的弦的类似长度): $string = (strlen($string) > 13) ? substr($string,0,10).'...' : $string; 所以你会得到一串最多13个字

how to get the last char of a string in PHP?

I need to get the last character of a string. Say I have "testers" as input string and I want the result to be "s". how can I do that in PHP? substr("testers", -1); // returns "s" substr($string, -1) Or by direct string access: $string[strlen($string)-1]; Note that this doesn't work for multibyte strings. If you need to work with multibyte string, consider using th

如何获取PHP中的字符串的最后一个字符?

我需要得到一个字符串的最后一个字符。 假设我有“测试者”作为输入字符串,我希望结果是“s”。 我怎么能在PHP中做到这一点? substr("testers", -1); // returns "s" substr($string, -1) 或者通过直接字符串访问: $string[strlen($string)-1]; 请注意,这不适用于多字节字符串。 如果您需要使用多字节字符串,请考虑使用mb_*字符串系列函数。

How to remove non

I need to remove all characters from a string which aren't in az AZ 0-9 set or are not spaces. Does anyone have a function to do this? 听起来你几乎已经知道你想要做什么,你基本上将它定义为一个正则表达式。 preg_replace("/[^A-Za-z0-9 ]/", '', $string); 对于unicode字符,它是: preg_replace("/[^[:alnum:][:space:]]/u", '', $string); Regular expression is your answer. $str = preg_replace('/[^a-

如何删除非

我需要从字符串中删除所有不在az AZ 0-9字符或不是空格。 有没有人有这样做的功能? 听起来你几乎已经知道你想要做什么,你基本上将它定义为一个正则表达式。 preg_replace("/[^A-Za-z0-9 ]/", '', $string); 对于unicode字符,它是: preg_replace("/[^[:alnum:][:space:]]/u", '', $string); 正则表达式就是你的答案。 $str = preg_replace('/[^a-zd ]/i', '', $str); i代表不区分大小写。 ^意思,并不是从一开始。

How to remove all specific characters at the end of a string?

只有当它是一段时间才能删除最后一个字符? $string = "something here."; $output = 'something here'; $output = rtrim($string, '.'); (参考:PHP.net上的rtrim) using rtrim replaces all "." at the end, not just the last character $string = "something here.."; echo preg_replace("/.$/","",$string); 为了只删除最后一个字符,并且不使用preg_replace我们可以将字符串视为一个char数组,如果它是一个

如何删除字符串末尾的所有特定字符?

只有当它是一段时间才能删除最后一个字符? $string = "something here."; $output = 'something here'; $output = rtrim($string, '.'); (参考:PHP.net上的rtrim) 使用rtrim替换所有“。” 最后,不只是最后一个字符 $string = "something here.."; echo preg_replace("/.$/","",$string); 为了只删除最后一个字符,并且不使用preg_replace我们可以将字符串视为一个char数组,如果它是一个点,则删除最后一个字符。 if ($str

Can someone explain me a php code

So i was searching it online but i couldn't find a basic explanation. I am new with php. So i am going to say what i understand out of this code. foreach is that it's using multiple $name and the AS makes the first variable the same as the second $key but then comes => which i don't understand. if $min higher than $val , $min = $val and the one under is the opposite. What i

有人可以解释我一个PHP代码

所以我在网上搜索,但我找不到一个基本的解释。 我是新的与PHP。 所以我要说出我对这段代码的理解。 foreach是它使用多个$ name,AS使第一个变量与第二个$ key相同,但是后来=>我不明白。 如果$ min高于$ val,$ min = $ val并且下面的是相反的。 什么是=>正在做什么? foreach($arr as $key => $val){ if($min > $val){ $min = $val; } if($max < $val){ $max = $val; } } 假设你有一个数组: $ar

What is the difference between => and

This question already has an answer here: Reference — What does this symbol mean in PHP? 18 answers Below link will provide you a full list of symbols and their usage. Reference - What does this symbol mean in PHP? Since you have asked, In short => is called T_DOUBLE_ARROW and is the separator for associative arrays, the '=>' created key/value pairs. -> is called &qu

=>和。之间的区别是什么?

这个问题在这里已经有了答案: 参考 - 这个符号在PHP中的含义是什么? 18个答案 以下链接将为您提供符号及其用法的完整列表。 参考 - 这个符号在PHP中的含义是什么? 既然你问了,简而言之 =>被称为T_DOUBLE_ARROW,是关联数组的分隔符,'=>'创建的键/值对。 ->被称为“对象运算符”或T_OBJECT_OPERATOR,当你想调用实例的方法或访问实例属性时使用它。 正如chandresh所说,但有例子: =>是

To convert foreach statements to for

How can you convert foreach -statements to for -loops in PHP? Examples to be used in your answers 1 foreach( $end_array[1]['tags'] as $tag ) and 2 foreach($end_array as $question_id => $row2) In both examples the expressions left to 'as' refer to an array. An array stores a mapping of keys to values. Both examples iterate through elements of this mapping. In the first e

将foreach语句转换为for

如何将foreach -statements转换为PHP中的-loops? 在你的答案中使用的例子 1 foreach( $end_array[1]['tags'] as $tag ) 和 2 foreach($end_array as $question_id => $row2) 在这两个例子中,留给'as'的表达式都是指数组。 数组存储键与值的映射。 这两个例子都遍历这个映射的元素。 在第一个示例中,您只对值(而不是映射到的键)感兴趣。 在每次迭代中,$ tag都指向“当前”值。 在第二个示例中