10 recommended articles about global variables

什么是全局变量？全局变量也称为外部变量，是在函数的外部定义的，它的作用域为从变量定义处开始，到这个程序文件的结尾。和其他编程语言不同，全局变量不是自动设置为可用的。上一章节我们介绍了php变量的范围的局部变量，在PHP中，由于函数可以视为单独的程序代码片段，所以局部变量会覆盖全局变量的能见度，因此在函数中无法直接调用全局变量。其代码如下所示的格式：

1. 关于变量的范围的10篇文章推荐

简介：什么是全局变量？全局变量也称为外部变量，是在函数的外部定义的，它的作用域为从变量定义处开始，到这个程序文件的结尾。和其他编程语言不同，全局变量不是自动设置为可用的。上一章节我们介绍了php变量的范围的局部变量，在PHP中，由于函数可以视为单独的程序代码片段，所以局部变量会覆盖全局变量的能见度，因此在函数中无法直接调用全局变量。其代码如下所示的格式：

2. 关于php静态全局变量的7篇文章推荐

简介：局部变量从存储方式上可分为动态存储类型和静态存储类型。函数中的局部变量，如不专门声明为 static 存储类别，默认都是动态地分配存储空间。其中的内部动态变量在函数调用结束后自动释放。如果希望在函数执行后，其内部变量依然保存在内存中，应当使用静态变量。在函数执行完毕以后，静态变量并不会消失，而是在所有对该函数的调用之间共享，即在函数再次执行时，静态变量将连续前次的结果继续运算，并且仅在脚本的执行期...

3. 关于PHP变量的详细介绍

简介：什么是全局变量？全局变量也称为外部变量，是在函数的外部定义的，它的作用域为从变量定义处开始，到这个程序文件的结尾。和其他编程语言不同，全局变量不是自动设置为可用的。上一章节我们介绍了php变量的范围的局部变量，在PHP中，由于函数可以视为单独的程序代码片段，所以局部变量会覆盖全局变量的能见度，因此在函数中无法直接调用全局变量。其代码如下所示的格式：

4. 如何实现JS代码的模块化

简介：因为在全局作用域中声明的变量和函数都自动成为全局对象Window的属性，这经常会导致命名冲突，全局变量越多，引入错误BUG的概率就越大！所以我们应当尽可能少地使用全局变量... ...，HTML5中国，中国最大的HTML5中文门户。

5. PHP中全局和超全局变量的区别

简介：这篇文章主要介绍了PHP全局变量与超级全局变量区别,较为详细的分析讲述了PHP全局变量与超级全局变量的概念,用法与使用区别,需要的朋友可以参考下

6. Detailed explanation of how to use global variables in PHP

# #Introduction: This article is a detailed analysis and introduction to several methods of using global variables in PHP. Friends in need can refer to

7. In php function The difference between local variables and global variables

## Introduction: Variables defined within a program are called local variables. It is only used within the program and disappears when the program ends. Variables defined outside the program are called global variables. They can be called by the program but will not disappear when the program ends.

8.

Detailed explanation of the difference between static static local variables and static global variables

Introduction: Local variables can be divided into dynamic storage types and static storage types in terms of storage methods. Local variables in a function, unless specifically declared as static storage class, will allocate storage space dynamically by default.

9.

What are global variables? Detailed explanation of global variable examples of the scope of PHP variables

##Introduction: Global variables are also called external variables. Defined outside the function, its scope starts from the variable definition to the end of the program file.

10.

In-depth analysis of pre-parsing and side effects in JavaScriptvar

##Introduction: Side effects of var There is a small difference between implicit global variables and explicitly defined global variables, which is the ability to leave variables undefined through the delete operator. Global variables created through var (created in any program outside of functions) cannot be deleted. Implicit global variables created without var (regardless of whether they are created in a function) can be deleted. This shows that, technically, implicit global variables are not really global variables

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