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JS教程

JS主页 JS简介 JS在哪里 JS输出 JS语句 JS语法 JS评论 JS变量 JS运算符 JS算术 JS分配 JS数据类型 JS函数 JS对象 JS活动 JS字符串 JS字符串方法 JS号 JS编号方法 JS数组 JS数组方法 JS数组排序 JS数组迭代 JS日期 JS日期格式 JS日期获取方法 JS日期设置方法 JS数学 JS 随机 JS布尔值 JS比较 JS条件 JS开关 JS循环 JS循环播放 JS Break JS类型转换 JS运算 JS正则 JS错误 JS范围 JS吊装 JS严格模式 JS此关键字 JS Let JS Const JS箭头功能 JS调试 JS样式指南 JS最佳做法 JS错误 JS性能 JS保留字 JS版本 JS ES5版 JS ES6版 JS JSON

JS表单

JS表单 Forms API

JS对象

对象定义 对象属性 对象方法 对象显示 对象访问器 对象构造器 对象原型 对象ECMAScript 5 Object Classes

JS函数

功能定义 功能参数 函数调用 函数调用 应用功能 功能闭包

JS HTML DOM

DOM简介 DOM方法 DOM文档 DOM元素 DOM HTML DOM CSS DOM动画 DOM事件 DOM事件监听器 DOM导航 DOM节点 DOM集合 DOM节点列表

JS浏览器BOM

JS窗口 JS屏幕 JS位置 JS历史记录 JS导航器 JS弹出警报 JS计时 JS Cookies

JS AJAX

AJAX简介 AJAX XMLHttp AJAX请求 AJAX响应 AJAX XML文件 AJAX PHP AJAX ASP AJAX数据库 AJAX应用程序 AJAX 示例

JS JSON

JSON简介 JSON语法 JSON与XML JSON数据类型 JSON解析 JSON Stringify JSON对象 JSON数组 JSON PHP JSON HTML JSON JSONP

JS Web APIs

Web API Intro Web History API Web Storage API Web Geolocation API

JS vs jQuery

jQuery选择器 jQuery HTML jQuery CSS jQuery DOM

JS 示例

JS 示例 JS HTML DOM JS HTML输入 JS HTML对象 JS HTML事件 JS浏览器 JS编辑器 JS 练习 JS测验 JS证书

JS 参考

JavaScript对象 HTML DOM对象


JavaScript 示例


What can JavaScript do?

示例 Explained


Where to Insert JavaScript

Where to Explained


JavaScript Output

Output Explained


JavaScript Syntax

Syntax Explained



JavaScript Statements

Statements Explained


JavaScript Comments

Comments Explained


JavaScript Variables

Variables Explained


JavaScript Arithmetic

Arithmetic Explained


JavaScript Assignment

Assignment Explained


JavaScript String Concatenation

Concatenation Explained


JavaScript Data Types

Data types Explained


JavaScript对象

Objects Explained


JavaScript Functions

Functions Explained


JavaScript Events

Events Explained


JavaScript Strings

Strings Explained


JavaScript Numbers

Numbers can be written with or without decimals Extra large or extra small numbers can be written with exponent notation Number are considered accurate only up to 15 digits 浮动ing point arithmetic is not always 100% accurate But it helps to multiply and divide by 10 Adding two numbers results in a new number Adding two numeric strings results in a concatenated string Adding a number and a numeric string also results in a concatenated string Adding a numeric string and a number also results in a concatenated string Common mistake when adding strings and numbers 1 Common mistake when adding strings and numbers 2 JavaScript will try to convert strings to numbers when dividing JavaScript will try to convert strings to numbers when multiplying JavaScript will try to convert strings to numbers when subtracting JavaScript will NOT convert strings to numbers when adding A number divided by a string is NaN (Not a Number) A number divided by a numeric string is a number The global JavaScript function isNaN() returns if a value is a number Using NaN in a mathematical operation will always return NaN Using NaN in a mathematical string operation will concatenate NaN NaN (Not a Number) is a number (Yes! typeof NaN returns number) Infinity is returned if you calculate a number outside the largest possible number Division by zero also generates Infinity Infinity is a number (typeof Infinity returns number) Constants, preceded by 0x, are interpreted as hexadecimal The toString() method can output numbers as hex, octal, and binary Numbers can be objects Numbers and objects cannot be safely compared Objects and objects cannot be safely compared

Numbers Explained


JavaScript Number Methods

Numbers Methods Explained


JavaScript Maths

Maths Explained


JavaScript Random

Random Explained


JavaScript Dates

Dates Explained


JavaScript Arrays

Arrays Explained


JavaScript Array Methods

Array Methods Explained


JavaScript Array Sort

Array Sort Explained


JavaScript Array Iteration

Array Iteration Explained


JavaScript Type Conversion

Type Conversion Explained


JavaScript Booleans

Booleans Explained


JavaScript Comparisons

Comparisons Explained


JavaScript Conditionals

Conditionals Explained


JavaScript Loops

Loops Explained


JavaScript Error Handling

Errors Explained


JavaScript Regular Expressions


JavaScript对象

Objects Explained


JavaScript 对象属性

对象属性 Explained


JSON对象

JSON 对象属性 Explained


JSON数组

JSON数组 Explained


JSON解析

JSON解析 Explained


JSON Stringify

JSON Stringify Explained


JSON PHP

JSON PHP Explained


JSON HTML

JSON HTML Explained


JSON JSONP

JSON JSONP Explained




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