


With the rapid development of the Internet, PHP language has become one of the most popular programming languages. PHP version 8.0 proposes a new constructor syntax, namely constructor attribute derivation. This article will introduce this new syntax, as well as its advantages and inconveniences for developers.
What is constructor property derivation?
In PHP version 8.0, you can automatically create and initialize member properties by adding access restrictions and variable declarators before the constructor parameters. Specifically, the declaration of class members can be merged with the definition of the constructor, thereby omitting the manual addition of member variables and the corresponding initialization operations in the constructor. This way, we can save a lot of code and time.
For example, here is an example of using constructor attribute deduction:
class Person { public function __construct( public string $name, public int $age, private string $gender = 'male' ) {} }
In the above code, we can see the parameter list of the constructor function __construct()
In, access restrictors and variable declarators are used to assign values to the class member attributes name
, age
, and gender
. Among them, the value of the default parameter $gender
is 'male'
.
Advantages of using constructor property derivation
- Simplifying code
By using constructor property derivation, we can combine the declaration and initialization steps of member properties Merged together, the code is simplified. At the same time, since there is no need to manually initialize in the constructor, errors and tedious code operations can also be avoided.
- Improve development efficiency
Constructor attribute derivation can save time and allow us to focus on solving the core problems of the program. We can build a class faster and the readability of the class is improved. This will significantly improve development efficiency.
- Better maintainability and code quality
Constructor property derivation syntax can improve code maintainability and quality. Because we can now directly define member properties of an object, the code becomes cleaner and more readable. At the same time, errors in the code are reduced because manual initialization is no longer required.
Inconveniences
Although the constructor attribute derivation syntax has many benefits, you should also pay attention to the inconveniences it may cause when using it:
- Can only be used in constructors
Constructor property derivation can only be used in constructors and cannot be used in other methods. Therefore, if you need to use member properties in other methods, you still need to declare and initialize them manually.
- Reduced readability
Although the constructor property derivation syntax can simplify the code, readability may decrease when the number and complexity of member properties increase. Therefore, to keep your code readable, careful consideration is needed before syntax is used.
Conclusion
Constructor property derivation syntax is a beneficial new feature in PHP version 8.0. By using this syntax, we can save a lot of code and time, improve development efficiency, and also improve the maintainability and code quality of the code. However, you also need to pay attention to the inconveniences it may bring to ensure the readability and quality of the code.
The above is the detailed content of New constructor syntax in PHP8.0: constructor attribute deduction. For more information, please follow other related articles on the PHP Chinese website!

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。

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。

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。

在php中,可以使用substr()函数来读取字符串后几个字符,只需要将该函数的第二个参数设置为负值,第三个参数省略即可;语法为“substr(字符串,-n)”,表示读取从字符串结尾处向前数第n个字符开始,直到字符串结尾的全部字符。

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。

查找方法:1、用strpos(),语法“strpos("字符串值","查找子串")+1”;2、用stripos(),语法“strpos("字符串值","查找子串")+1”。因为字符串是从0开始计数的,因此两个函数获取的位置需要进行加1处理。


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

SublimeText3 English version
Recommended: Win version, supports code prompts!

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

WebStorm Mac version
Useful JavaScript development tools

SublimeText3 Linux new version
SublimeText3 Linux latest version

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.
