Explain PHP/MySQL in Simple Terms

This question already has an answer here: How does PHP 'foreach' actually work? 7 answers It's a foreach loop. So it can be translated to... for every object in the $row variable, assign that object to the new variable $name , with its corresponding value as $value That will loop N times, where N is the number of rows returned. Each time the loop is iterated, the $name and

用简单的术语解释PHP / MySQL

这个问题在这里已经有了答案: PHP'foreach'如何实际工作? 7个答案 这是一个foreach循环。 所以它可以被翻译成... 对于$row变量中的每个对象,将该对象分配给新变量$name ,其相应的值为$value 这将循环N次,其中N是返回的行数。 每次迭代循环时, $name和$value变量都会重新初始化为新行的内容。

Passing by reference assignment php

This question already has an answer here: How does PHP 'foreach' actually work? 7 answers Without delving into the technical details too much, the basic idea here is that you have made $ref a reference to $row . Specifically, $row is at some memory address. If you do a simple assignment $ref = $row; Then $ref is a copy of $row . If you change one, it will not change the other $

通过引用分配php

这个问题在这里已经有了答案: PHP'foreach'如何实际工作? 7个答案 没有深入研究技术细节,这里的基本思想是你已经使$ref成为$row的引用。 具体来说, $row某个内存地址。 如果你做了一个简单的任务 $ref = $row; 然后$ref是$row的副本 。 如果你改变一个,它不会改变另一个 $row = &$ref; $ref现在指向$row 。 所以他们本质上是同一个变量。 他们指向相同的记忆位置(过于简化,所以你明白了)。

Increasing array elements while in foreach loop in php?

This question already has an answer here: How does PHP 'foreach' actually work? 7 answers Foreach copies structure of array before looping(read more), so you cannot change structure of array and wait for new elements inside loop. You could use while instead of foreach . $arr = array(); $arr['b'] = 'book'; reset($arr); while ($val = current($arr)) { print "key=".key($arr).P

在PHP的foreach循环中增加数组元素?

这个问题在这里已经有了答案: PHP'foreach'如何实际工作? 7个答案 Foreach在循环之前复制数组的结构(读取更多),因此您不能更改数组的结构并等待循环内的新元素。 你可以使用while不是foreach 。 $arr = array(); $arr['b'] = 'book'; reset($arr); while ($val = current($arr)) { print "key=".key($arr).PHP_EOL; if (!isset($arr['a'])) $arr['a'] = 'apple'; next($arr); }

Unexpected behaviour of current() in a foreach loop

This question already has an answer here: How does PHP 'foreach' actually work? 7 answers Why does it start with B? Since 5.2 foreach (reliably) advances the array pointer before the loop body starts. See also the FE_RESET opcode. $list = array("A", "B", "C","D"); foreach ($list as $var) { break; } var_dump(current($list)); Output: B This may have something to with how the

foreach循环中current()的意外行为

这个问题在这里已经有了答案: PHP'foreach'如何实际工作? 7个答案 为什么它以B开头? 由于foreach (可靠地)在循环体开始前提前数组指针。 另请参阅FE_RESET操作码。 $list = array("A", "B", "C","D"); foreach ($list as $var) { break; } var_dump(current($list)); 输出: B 这可能与ZEND_OP_DATA伪操作码的工作方式有关(没有真正记录)。 为什么current()一直给出相同的值? 在循环开始之

PHP foreach inside loop on array that added inside the loop

i am php newbie,i practice on arrays. I created a foreach on some string that i converted to array,then inside the foreach i added more 2 arrays one before the end of the loop and one random. here the code: <?php //Some string to practice on $links = " http://hi.co.il<br> ?????? ht tp://hi.co.il<br> ????? http://hi.co.il<br> http://hi.co.il<br&

在foreach循环内添加循环的PHP foreach

我是PHP新手,我在数组上练习。 我创建了一个字符串的foreach,我转换为数组,然后在foreach中,我在循环结束之前添加了更多2个数组,然后一个随机数。 代码如下: <?php //Some string to practice on $links = " http://hi.co.il<br> ?????? ht tp://hi.co.il<br> ????? http://hi.co.il<br> http://hi.co.il<br> http://hi.co.il<br> http://mega.co.il&

Foreach loop not updating the values

I've for a few forms on the page. Before rendering them in my views, I create them dynamically in PHP with their buttons and elements. I want to adjust the tabindexes dynamically, so basically once I have all the forms ready at the end of the PHP script, I do the following: public function fixTabindexes($forms) { $tabindex = 1; $forms = count($forms) > 1 ? $forms : [$for

Foreach循环不更新值

我在页面上有几个表单。 在我的视图中呈现它们之前,我使用它们的按钮和元素动态地在PHP中创建它们。 我想动态地调整tabindexes,所以基本上,一旦我在PHP脚本的末尾准备好了所有的表单,我会执行以下操作: public function fixTabindexes($forms) { $tabindex = 1; $forms = count($forms) > 1 ? $forms : [$forms]; foreach($forms as $form) { foreach($form['form'] as $element) {

Replacing array value in foreach loop

What am I doing wrong here? It's so simple and I'm overlooking something. I'm trying to replace the value of an array key within a foreach loop: $arr = array(); $arr['firstimg'] = '123'; $arr['secondimg'] = '456'; $arr['thirdimg'] = '789'; foreach ($arr as $key => $value) { if ($key == 'secondimg') { $value = '000'; } } print_r($arr); The array is staying t

在foreach循环中替换数组值

我在这里做错了什么? 这很简单,我忽略了一些东西。 我试图在foreach循环中替换数组键的值: $arr = array(); $arr['firstimg'] = '123'; $arr['secondimg'] = '456'; $arr['thirdimg'] = '789'; foreach ($arr as $key => $value) { if ($key == 'secondimg') { $value = '000'; } } print_r($arr); 阵列保持不变。 变量$value的范围是循环。 您需要更新$arr[$key] 。 或者,你可以声明循环

Split sprintf() in foreach loop

A simple question i can't figure out. I'm having this simple sendmail script in php. But i need the printet array (that prints the body of the email) to be splittet up. What is the simplest solution to make the outcome from the foreach loop be: 1. In the first 4 posts in the array, only the value and not the key from the post is printet 2. The rest of the array is printet, both ke

在foreach循环中拆分sprintf()

一个简单的问题,我无法弄清楚。 我在php中有这个简单的sendmail脚本。 但我需要printet数组(打印电子邮件的正文)被分割。 使foreach循环的结果最简单的解决方案是: 1.在数组中的前4个帖子中,只有帖子的值而不是帖子的键是printet 2.数组的其余部分是printet,包括键和值。 我目前使用这个: foreach($fields as $a => $b){ $body .= sprintf("%20s: %sn",$b,$_REQUEST[$a]); } 似乎无法摆脱它的困扰。 任

Find the last element of an array while using a foreach loop in PHP

I am writing a SQL query creator using some parameters. In Java, it's very easy to detect the last element of an array from inside the for loop by just checking the current array position with the array length. for(int i=0; i< arr.length;i++){ boolean isLastElem = i== (arr.length -1) ? true : false; } In PHP they have non-integer indexes to access arrays. So you must itera

在PHP中使用foreach循环时查找数组的最后一个元素

我正在使用一些参数编写SQL查询创建器。 在Java中,通过使用数组长度检查当前数组的位置,可以很容易地从for循环内检测数组的最后一个元素。 for(int i=0; i< arr.length;i++){ boolean isLastElem = i== (arr.length -1) ? true : false; } 在PHP中,它们具有非整数索引来访问数组。 所以你必须使用foreach循环迭代一个数组。 当你需要做出一些决定(在我的情况下追加或/和参数,同时构建查询)时,这会变

Hidden Features of PHP?

I know this sounds like a point-whoring question but let me explain where I'm coming from. Out of college I got a job at a PHP shop. I worked there for a year and a half and thought that I had learned all there was to learn about programming. Then I got a job as a one-man internal development shop at a sizable corporation where all the work was in C#. In my commitment to the position I

PHP的隐藏功能?

我知道这听起来像是一个指责问题,但让我解释我来自哪里。 大学毕业后,我在一家PHP商店找到了一份工作。 我在那里工作了一年半,认为我已经了解了所有有关编程的知识。 然后,我在一家大公司开展了一个单人内部开发工作,所有工作都在C#中进行。 在我对这个职位的承诺中,我开始阅读大量的博客和书籍,并很快意识到我以为我知道所有事情都是错误的。 我学习了单元测试,依赖注入和装饰器模式,松散耦合的设计原理,继承