Table of Contents
回复内容:
Home Backend Development PHP Tutorial 作为一名PHPER,您如何命名临时变量

作为一名PHPER,您如何命名临时变量

Jun 06, 2016 pm 08:47 PM
php

如题,在编写代码的时候,总会遇到一些临时变量
那么你通常会选择给临时变量取个什么名字,
比如

$foo, $a, $x

等等?

回复内容:

如题,在编写代码的时候,总会遇到一些临时变量
那么你通常会选择给临时变量取个什么名字,
比如

$foo, $a, $x

等等?

临时变量名,主要就是看用在哪里的
如果是用在循环中的肯定是

$i, $j, $k

如果是用foreach中的话,多数情况会是

$k, $v, $key, $val

如果是用临时使用的

$temp, $t

真不知道是干什么用,还要用的话,一般我叫

$ignore_me

另外就是根据类型叫名称

$int, $num, $str, $arr

简单易读有意义的单词

临时变量跟普通变量一样命名,变量的生命周期不从变量名体现。

<code>    一个变量既然存在,就一定是不能删的。他必然有类型,他必然有用途,既然有类型有用途,他必须有自己的名字,哪怕是 $intNumber、$keyOfUsersArray、$tempFileUploaded 也比 $tmp1、$tempFile 好。

    最糟糕的两个变量名是 $data1 和 $data2,我认为再次就是 $tmp 、 $temp 了。


    如果你们公司只有一个临时工,那么你可以叫他 "临时工" ,这没问题。但是如果新来了一个临时工呢?叫 "新来的临时工" ?再来怎么办?所以最好的办法是一开始就给他们取个名字。比如 "胖王","李花匠","小寸头","王大力"...
</code>
Copy after login

补充一种,《重构——改善既有代码的设计》中介绍的一种去除临时变量的方法——使用查询代替临时变量(Replace Temp With Query):

重构前:

...
$basePrice = $this->quantity * $this->itemPrice; //临时变量$basePrice

if ($basePrice > 1000) {
    return $basePrice * 0.95;
} else {
    return $basePrice * 0.38;
}
...
Copy after login

重构后:

...
if ($this->basePrice() > 1000) {
    return $this->basePrice() * 0.95;
} else {
    return $this->basePrice() * 0.38;
}

...
//用于代替临时变量的查询式
public function basePrice() {
    return $this->quantity * $this->itemPrice;
}
...
Copy after login

书中所述的使用动机:
临时变量的问题在于:它们是暂时的,而且只能在所属函数内使用.由于临时变量只有在所属函数内才可见,所以它们会驱使你写出更长的函数,因为只有这样你才能访问到想要访问的临时变量.如果把临时变量替换为一个查询式(query method),那么同一个class中的所有函数都将可以获得这份信息.这将带给你极大帮助,使你能够为这个class编写更清晰的代码.

循环里的和@lazyboy的差不多,其他的就是变量名加_tmp后缀

不明白为什么非要有“临时”的概念,脚本运行完所有变量全销毁,运行的时候,我们很少会主动unset它,讨论他的生命周期又有什么意义呢。

至于作用域内的,这个随心情呗。

$temp
$tmp

就我来说,如果是单独一个临时变量我会用_完事,多个就要带点含义了,不过总是要以_开头。呵呵。

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian Dec 24, 2024 pm 04:42 PM

PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati

How To Set Up Visual Studio Code (VS Code) for PHP Development How To Set Up Visual Studio Code (VS Code) for PHP Development Dec 20, 2024 am 11:31 AM

Visual Studio Code, also known as VS Code, is a free source code editor — or integrated development environment (IDE) — available for all major operating systems. With a large collection of extensions for many programming languages, VS Code can be c

7 PHP Functions I Regret I Didn't Know Before 7 PHP Functions I Regret I Didn't Know Before Nov 13, 2024 am 09:42 AM

If you are an experienced PHP developer, you might have the feeling that you’ve been there and done that already.You have developed a significant number of applications, debugged millions of lines of code, and tweaked a bunch of scripts to achieve op

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

How do you parse and process HTML/XML in PHP? How do you parse and process HTML/XML in PHP? Feb 07, 2025 am 11:57 AM

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

PHP Program to Count Vowels in a String PHP Program to Count Vowels in a String Feb 07, 2025 pm 12:12 PM

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

See all articles