Home Backend Development PHP Tutorial Summarize the aspects that need to be paid attention to when creating an array

Summarize the aspects that need to be paid attention to when creating an array

Jun 12, 2017 am 11:07 AM

In JavaScript, you can use the Array constructor to create an array, or use the array literal [], the latter is the preferred method. The Array object inherits from Object.prototype, and executing the typeof operator on the array returns object instead of array. However,[] instanceof Array also returns true. In other words, the implementation of array-like objects is more complex, such as strings objects and arguments objects. The arguments object is not an instance of Array, but has a length attribute and can obtain values ​​through indexes, so it can be looped like an array. In this article, I'll review some of the array prototype methods and explore their uses. Loop: .forEach; Judgment: .some and .every; Distinguish between .join and .concat; Implementation of stack and queue: .pop, .push, .shift, and .unshift; Model mapping: .map; Query: .filter; Sorting: .sort; Calculation:

1. Introduction to JavaScript native array functions

Summarize the aspects that need to be paid attention to when creating an array

# #Introduction: In JavaScript, you can use the Array constructor to create an array, or use the array literal, the latter is the preferred method. The Array object inherits from Object.prototype, and executing the typeof operator on the array returns object instead of array. However, instanceof Array also returns true. ... . ..., HTML5 China, China's largest HTML5 Chinese portal.

2. PHP Array Basics

Summarize the aspects that need to be paid attention to when creating an array

# #Introduction: 1. How to define an array: There are two main ways to create an array in PHP. Let’s take a look at how to create an array (1) Create an array by directly assigning a value to each element. The format is: $arrayname[key]...

3.

How to use javascript to create arrays in batches

Summarize the aspects that need to be paid attention to when creating an array

Introduction: JavaScript has many ways to create arrays in batches. In order to measure their performance, different methods are used to create an array with a length of 100000, and the keys and values ​​are equal.

4.

Details on how to create arrays in batches using JavaScript (picture)

Summarize the aspects that need to be paid attention to when creating an array

Introduction: JavaScript has many ways to create arrays in batches. In order to measure their performance, I used different methods to create an array with a length of 100000, and the keys and values ​​are equal. Today I will give you Share the method of creating arrays in batches based on js, let’s take a look together

5.

Details code examples of interesting JavaScript native array functions

Summarize the aspects that need to be paid attention to when creating an array

#Introduction: In JavaScript, you can use the Array constructor to create an array, or use the array literal [], the latter is the preferred method. The Array object inherits from Object.prototype, and executing the typeof operator on the array returns object instead of array. However, []instanceof Array also returns true. In other words, the implementation of array-like objects is more complex, such as strings objects and arguments objects. The arguments object is not an instance of Array, but has a length attribute and can be retrieved through index..

6.

PHP Basic Tutorial Eight Arrays

Summarize the aspects that need to be paid attention to when creating an array

简介:本节讲解内容数组的介绍数组的创建数组的动态增长数组的遍历数组的相关函数数组运算符在前面我们所学的不管是变量和常量,都是一个个单个的数据,而有时候我们有这样的需求,需要把一些相同类型的数值或一些不相干的数值,合理的存储起来,而用到的时候可以按照某种规则取出数据。这时候前面的变量等就不能满足要求,在这里就是用到数组。数组的介绍PHP中的数组和别的语言的数组不一样,这也是PHP语言语法的

7. JS—数组

Summarize the aspects that need to be paid attention to when creating an array

简介:数组(Array对象) 数组是一种对象。数组是值的有序集合。每个值叫做元素(可以是任意类型),每个元素在数组中都有一个位置,以数字表示,称为索引(0—232-2)。 一、创建数组 1.使用数组字面量(直接量) var empty=[];//空数组 var misc=[1.1,true,”a”,[1,{x:1,y:2}]];//元素类型不同 var count=[1,,2];//有3个元素,中间 ...

8. php数组基础

Summarize the aspects that need to be paid attention to when creating an array

简介:如何定义数组:在php中创建数组主要有两种方式,下面就让我们来看看如何创建一个数组

9. PHP array() 数组

Summarize the aspects that need to be paid attention to when creating an array

简介:array() 创建数组,带有键和值。如果在规定数组时省略了键,则生成一个整数键,这个 key 从 0 开始,然后以 1 进行递增。   要用 array() 创建一个关联数组,可使用 => 来分隔键和值。     要创建一个空数组,则不传递参数给   array():     $new = array();  注意:array()   实际上是一种语言结构 (language constru ...

10. php数组学习之一

Summarize the aspects that need to be paid attention to when creating an array

简介:php数组学习 数组:关键字和值的集合,同一php数组可以存放多种不同数据类型的值,数组下标从零开始 创建数组的几种方式: (1)      $arr[0]=1;//数组元素      $arr[1]=2.8;      ......       (2)        $arr = array(1,2.8,"str",.....);        (3)//可以自己指定数组元素的 ...

【相关问答推荐】:

数组 - java.lang.reflect.Array类的意义?

php - 如何理解这句话的语法规则?

javascript - js中怎么在创建数组的时候就赋值?

数组赋值问题?

用[]创建数组

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