PHP's include() and require() are two methods of including external files. Many beginners may not understand the difference between these two methods. The following summarizes the differences between PHP include() and require():
1: Loading failures are handled differently:
include() will generate a warning, while require() will cause a fatal error (an error occurred , the script stops executing)
require() : If the file does not exist, a fatal error will be reported. The script will stop executing
include() : If the file does not exist, a warning will be given, but the script will continue to execute
Here Special attention should be paid to: when the include() file does not exist, the script continues to execute. This situation only occurs before PHP 4.3.5. It is recommended to use
require_once() and include_once() to detect whether the file is duplicated. Include. 2.php performance
For include(), the file must be read and evaluated every time when include() is executed;
For
require(), the file is only processed once (in fact, the file The content replaces the require() statement). This means that if you have code that contains one of these instructions and code that may be executed multiple times, it is more efficient to use
require(). On the other hand, if you read a different file each time the code is executed, or have a loop that iterates through a set of files, use include(),
because you can set a variable for the file name you want to include. This variable is used when the parameter is include().
3. The two methods provide different flexibility of use.
require is used like require(“./inc.php”); . It is usually placed at the front of the PHP program. Before the PHP program is executed, it will first read in the file specified by require and make it a part of the PHP program web page. include is used like include(“./inc/.php”); . Generally placed in the processing section of process control. The PHP program web page reads the include file only when it reads it. In this way, the process of program execution can be simplified.
require will be included even when the condition bit is FALSE, and include will only be executed when it reaches the changed position. The
require_once() statement includes and runs the specified file during script execution. This behavior is similar to the require() statement, the only difference is that if the code in the file is already included, it will not be included again. The function of require_once() function is almost the same as require() include_once() statement includes and runs the specified file during script execution. This behavior is similar to the include() statement, the only difference is that if the code in the file is already included, it will not be included again. The function of include_once() is almost the same as include(). The function of_once is to check whether the file has been loaded before. If it has not been loaded, load it. If it has been loaded, it will not be loaded again. For example, a file defines a If the file is loaded twice, an error will occur. The above is the difference between the PHP include() and
require
() methods.
The above introduces the difference between the PHP include and require methods, including the require content. I hope it will be helpful to friends who are interested in PHP tutorials.

vue3+vite:src使用require动态导入图片报错和解决方法vue3+vite动态的导入多张图片vue3如果使用的是typescript开发,就会出现require引入图片报错,requireisnotdefined不能像使用vue2这样imgUrl:require(’…/assets/test.png’)导入,是因为typescript不支持require所以用import导入,下面介绍如何解决:使用awaitimport

php把负数转为正整数的方法:1、使用abs()函数将负数转为正数,使用intval()函数对正数取整,转为正整数,语法“intval(abs($number))”;2、利用“~”位运算符将负数取反加一,语法“~$number + 1”。

实现方法:1、使用“sleep(延迟秒数)”语句,可延迟执行函数若干秒;2、使用“time_nanosleep(延迟秒数,延迟纳秒数)”语句,可延迟执行函数若干秒和纳秒;3、使用“time_sleep_until(time()+7)”语句。

php除以100保留两位小数的方法:1、利用“/”运算符进行除法运算,语法“数值 / 100”;2、使用“number_format(除法结果, 2)”或“sprintf("%.2f",除法结果)”语句进行四舍五入的处理值,并保留两位小数。

判断方法:1、使用“strtotime("年-月-日")”语句将给定的年月日转换为时间戳格式;2、用“date("z",时间戳)+1”语句计算指定时间戳是一年的第几天。date()返回的天数是从0开始计算的,因此真实天数需要在此基础上加1。

php判断有没有小数点的方法:1、使用“strpos(数字字符串,'.')”语法,如果返回小数点在字符串中第一次出现的位置,则有小数点;2、使用“strrpos(数字字符串,'.')”语句,如果返回小数点在字符串中最后一次出现的位置,则有。

方法:1、用“str_replace(" ","其他字符",$str)”语句,可将nbsp符替换为其他字符;2、用“preg_replace("/(\s|\ \;||\xc2\xa0)/","其他字符",$str)”语句。

php字符串有下标。在PHP中,下标不仅可以应用于数组和对象,还可应用于字符串,利用字符串的下标和中括号“[]”可以访问指定索引位置的字符,并对该字符进行读写,语法“字符串名[下标值]”;字符串的下标值(索引值)只能是整数类型,起始值为0。


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