C语言和PHP语法相异点-PHP Tutorial-php.cn

Home

Backend Development

PHP Tutorial

C语言和PHP语法相异点

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 20, 2016 pm 12:57 PM

C语言和PHP语法相异点技术

maybe yes 发表于2015-02-05 16:09

PHP 的语法规则和 C 语言语法规则非常的相似，PHP 中很多内部函数调用的就是原生的 C 语言函数。由于两种语言的运行方式不同，导致在某些情况下语法也有一些差异，下面列举几个。

获取全局变量方式不同

在作用域中获取全局变量的值，PHP 必须借助 global 关键字获取或者使用超全局变量 $GLOBAL 去访问外部变量值。C语言相对简单点，在局部作用域中若没有相同的变量名称则访问的就是外部声明的变量的值。

初始化（Initializer）变量不同

C 语法中全局变量初始化时，只能使用常量表达式（Constant Expression）初始化。在 PHP 语法中，初始化变量可以使用任意表达式。

函数嵌套不同

C 语言不允许嵌套定义函数，在一个函数体中可以声明另一个函数，但不能定义另一个函数（但gcc的扩展特性允许嵌套定义函数）。PHP 允许嵌套定义函数，可以经常看到在函数体中或者 IF 语句中有定义了另一个函数，只要能保证调用嵌套函数的顺序在运行了嵌套语句之后即可。

阅(91)评(0)查看评论

Statement

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

Working with Flash Session Data in LaravelMar 12, 2025 pm 05:08 PM

Laravel simplifies handling temporary session data using its intuitive flash methods. This is perfect for displaying brief messages, alerts, or notifications within your application. Data persists only for the subsequent request by default: $request-

cURL in PHP: How to Use the PHP cURL Extension in REST APIsMar 14, 2025 am 11:42 AM

The PHP Client URL (cURL) extension is a powerful tool for developers, enabling seamless interaction with remote servers and REST APIs. By leveraging libcurl, a well-respected multi-protocol file transfer library, PHP cURL facilitates efficient execution of various network protocols, including HTTP, HTTPS, and FTP. This extension offers granular control over HTTP requests, supports multiple concurrent operations, and provides built-in security features.

Simplified HTTP Response Mocking in Laravel TestsMar 12, 2025 pm 05:09 PM

Laravel provides concise HTTP response simulation syntax, simplifying HTTP interaction testing. This approach significantly reduces code redundancy while making your test simulation more intuitive. The basic implementation provides a variety of response type shortcuts: use Illuminate\Support\Facades\Http; Http::fake([ 'google.com' => 'Hello World', 'github.com' => ['foo' => 'bar'], 'forge.laravel.com' =>

Discover File Downloads in Laravel with Storage::downloadMar 06, 2025 am 02:22 AM

The Storage::download method of the Laravel framework provides a concise API for safely handling file downloads while managing abstractions of file storage. Here is an example of using Storage::download() in the example controller:

12 Best PHP Chat Scripts on CodeCanyonMar 13, 2025 pm 12:08 PM

Do you want to provide real-time, instant solutions to your customers' most pressing problems? Live chat lets you have real-time conversations with customers and resolve their problems instantly. It allows you to provide faster service to your custom

Explain the concept of late static binding in PHP.Mar 21, 2025 pm 01:33 PM

Article discusses late static binding (LSB) in PHP, introduced in PHP 5.3, allowing runtime resolution of static method calls for more flexible inheritance.Main issue: LSB vs. traditional polymorphism; LSB's practical applications and potential perfo

PHP Logging: Best Practices for PHP Log AnalysisMar 10, 2025 pm 02:32 PM

PHP logging is essential for monitoring and debugging web applications, as well as capturing critical events, errors, and runtime behavior. It provides valuable insights into system performance, helps identify issues, and supports faster troubleshoot

How to Register and Use Laravel Service ProvidersMar 07, 2025 am 01:18 AM

Laravel's service container and service providers are fundamental to its architecture. This article explores service containers, details service provider creation, registration, and demonstrates practical usage with examples. We'll begin with an ove

See all articles

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

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)

2 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

How Long Does It Take To Beat Split Fiction?

1 months agoByDDD

R.E.P.O. Save File Location: Where Is It & How to Protect It?

1 months agoByDDD

R.E.P.O. Best Graphic Settings

2 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Assassin's Creed Shadows: Seashell Riddle Solution

1 weeks agoByDDD

Hot Tools

EditPlus Chinese cracked version

Small size, syntax highlighting, does not support code prompt function

SublimeText3 English version

Recommended: Win version, supports code prompts!

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.