PHP nested function and anonymous function scope issues

{Code...} All functions and classes in PHP have global scope and can be defined within a function and called outside it, and vice versa. Why can function b obtain the local variables of function a by passing parameters? {Code...} Similarly, why does the anonymous function also obtain external variab...

phpcn_u1582 2017-05-18 10:45:34 0  1  642

c++ - Can functions with the same name with different parameters in a derived class be declared as virtual functions

When the base class and the derived class have functions with the same name, regardless of whether the number of parameters is the same or different, the subclass object will always directly call the function of the same name of the derived class. If you want to call the function of the same name of...

世界只因有你 2017-06-10 09:48:57 0  1  1334

There is an error in having contiguous paging function paginate during laravel data operation. What's going on?

The database data is like this: I want to use the having statement to get out the ones with counts > 0; paging is used, so having is followed by the paging function paginate, but an error is reported like this: If I follow having with the get() function, there is no problem. You can find data wit...

某草草 2017-05-16 16:49:05 0  1  940

PHP code to write a function to find the correlation coefficient?

PHP code to write a function to find the correlation coefficient?

时光正好 2018-04-12 19:02:34 0  0  919

PHP substr() function

How to understand the usage of PHP substr() function: If the start parameter is a negative number and length is less than or equal to start, then length is 0. This sentence

ringa_lee 2017-05-24 11:30:51 0  2  809

How to change it so that the data is displayed on the page in reverse order, that is, the latest data is displayed at the front (code on the Internet)

<?php //Paging function function news($pageNum = 1, $pageSize = 5) { $array = array(); // $coon = mysqli_connect('rm-bp108931c0786t58eko.mysql.rds.a

肆意。 2019-03-30 10:48:16 0  2  1345

How does the parameter $class of the spl_autoload_register(function($class){} callback function identify the class to be loaded?

How does the parameter $class of the spl_autoload_register(function($class){} callback function identify the class to be loaded? Can automatically loaded classes under the same root file be identified by $class?

安超 2023-01-13 22:07:10 0  1  691

Preview of the teaching course on September 10, 2018: How to implement paging query data table and classification query for class encapsulation in PHP

Preview of the teaching content of the third online class of PHP Chinese website on September 10, 2018: 1. Teaching topic: How to use PHP to implement paging query data tables? Encapsulate classification queries into classes to achieve code reuse. For more detailed knowledge points, please pay atten...

藏色散人 2018-09-10 10:02:37 0  0  1294

php - A certain function can be implemented using a function. Is it necessary to use a class to implement it?

I use PHP. Most of the functions in the project I am writing now are encapsulated into functions. When needed, just require, and then pass the parameters to call the function. I don’t know if this will be bad. Is it still possible? Should we use classes to implement it? Take the homepage of the webs...

滿天的星座 2017-05-31 10:33:09 0  10  813

php - Questions about defining variables

I am a beginner. I used phpstorm to write the following code at home. The code that runs without error is as follows: &lt;?php$x=5; // Global variable function myTest(){ {code...} }myTest( );echo "&lt;p&gt;Test function external variables:&lt;p&gt;";echo "Variable ...

过去多啦不再A梦 2017-06-07 09:23:08 0  5  741

Using classList in Javascript function to add CSS classes, but styles conflict because latest class does not take precedence

My function counts the number of cards visible on the screen and if all are displayed then adds arrow-up class to my icon and if some cards are still hidden from user then arrow-down icon is added. constshowMoreIcon=document.querySelector('.cta-icon');functionmyFunction(){constbtnIcon=cardsOnShow>...

P粉738821035 2023-09-10 17:10:38 0  2  583

Extract variables from php file from function in another file

I have a php file in the root directory and I want to retrieve a variable from a function in another php file. I need it for SQL queries. My php file is in the root directory <?phprequiredirname(__FILE__).'/config/config.inc.php';require'modules/pricefrom/pricefrom.php';$lowestPrice=Db::getInstan...

P粉198670603 2023-09-07 13:33:37 0  1  589

httprequest gets PHP functions and variables

How to access and receive variables from a PHP file using HTTP requests? I receive an HTTP request connected to my .PHP file. Next what I want to do is for example reference I want to receive $testvariable=1; back but I don't know where to start. The HTTP parameters don't actually let me reference t...

P粉920835423 2024-01-29 14:00:32 0  1  421

Can PHP directly call functions in a class without using new?

I have to do something new every time, which is very unaccustomed. Can I use the functions in the class directly? The purpose of using the class is to look at the static attributes inside, so that when operating redis or mysql, automatic connection and connection reuse can be realized without the ne...

只争朝夕 2022-12-23 12:12:24 0  1  1974

Fatal error: Call to undefined function gmp_sign() in PHP

Fatal error: Call to undefined function gmp_sign() in PHP; trying to use the gmp_sign function in my file to find out the sign of a value

P粉848442185 2023-07-17 18:43:05 0  1  485

Learn how to effectively use compound selectors in CSS pseudo-class functions: host-context(<selector>)

In the MDN documentation, :host-context() is defined as: :host-context() CSS pseudo-class function selects the shadow host of the shadow DOM containing the CSS it is in (so you can select custom elements from its shadow DOM ) - but only works if the selector given as a function parameter matches the...

P粉268284930 2023-09-16 15:49:33 0  1  1024

How to call PHP function through JavaScript?

I'm trying to call a PHP function via JavaScript from an external PHP file. My code is relatively long, so I'll write a sample code here. This is my PHP code: This is my JavaScript code: var phpadd = add(1,2); // Call the phpadd function var phpmult = mult(1,2); // Call the phpmult function var ph.....

P粉133321839 2023-07-30 18:57:00 0  2  599

To implement the addition of PHP, call the addition function of PHP, first assign the values ​​​​1 and 2 to id and id1, and then call the addition function. The parameters in parentheses

<?php$id = '1'; Define a parameter $id2 = '2'; define a parameter echo bcadd($id,$id2,3); call the php addition function and output it. The third parameter is the number of digits to be retained after the decimal point.

和 2019-03-28 18:26:18 0  0  945

It seems that higher versions of PHP no longer support the mysql_connect function.

It seems that higher versions of PHP no longer support the mysql_connect function.

俊羽 2017-07-29 23:33:40 0  5  1411

When there is multiple user data, how to use classes to handle multiple

class usermodel{ public $userList;   public $id; public $name; public function _init(){   $this->userList=include_once './123.php'; } public function get_name(){ 

落叶. 2019-08-11 14:57:18 0  0  878