JavaScript基础知识总结的相关内容

文章 2022-09-24 来自：开发者社区

JavaScript的基础知识总结（3）

一、表达式与运算符：     1、对于属性访问表达式：var arr = {first:"hh","second":"gg",third:null};alert(arr.first+"=="+arr["second"]+"=="+arr["third"]+"=="+arr.fourth);//hh==gg==null==undefined如果命名的属性不存在，那么访问...

文章 2022-09-24 来自：开发者社区

1、JavaScript的数据类型分为两类：原始类型和对象类型；原始类型包括：数字，字符串，布尔值，null和undefined; （都是不可变类型，值不可以修改）对象类型：普通对象和函数；函数可使用new新建对象，即构造函数；每个构造函数定义了一类对象--由构造函数初始化的对象组成的集合；类可以看做是对象类型的子类型，javascript语言定义的类主要有：数组Array,函数Function....

文章 2017-11-09 来自：开发者社区

JavaScript一些基础性知识总结

1.看两个循环： <script type="text/javascript"> var result=0; for(var i=0;i <=100;i++) { result += i; } alert(result); </script> <script type="text/javascript"> v...

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更新时间 2022-11-29 14:26:09

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