随笔分类 - JS
摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title></head><body><div id="i1" class="c1">yuan</div><div class="c1">rain</
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <style> #i1{ color: red; } </style> <script> function show() { // 查找
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // window.alert("磁盘已满") // window.confirm("是否继续") // window
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // 函数声明 function foo(){ // 函数体 console.log("hello huchangxi
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> console.log(Math.abs(-100)) // 100 #绝对值 console.log(Math.ce
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // 获取当前日期对象 var date = new Date() console.log(date) // Sat
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title>、 <script> // 方法1 var obj = new Object(); obj.name = "huchangxi" obj.
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> var arr = ["huchangxi",23,true] console.log(arr.length) //
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // 条件循环 遍历循环 // while for // 无限循环 /*while (true){ console.l
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> var x = 10 // var ret = x++ // x +=1 // x = x+1 //先赋值再计算 va
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> var age = 20 // 成年人观看 if (age > 18){ console.log("成年人观看") }
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> var num1 ="3.14" var ret1 = parseFloat(num1) // #将字符串转换为数字
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // undefined场景1 var a; console.log(a,typeof a) // undefined
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摘要：知识点1：除数字0和字符串为空外全是true<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> var ret = 2 > 1 console.log(ret,typeo
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // 声明字符串 var s1 = "hellow huchangxi" var s2 = 'hellow hucha
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> var num1 = 3.14 var num2 = 100 console.log(typeof num1,type
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摘要：变量 1 2 3 4 5 6 7 8 9 格式: // 方式1 先声明再赋值 var 变量名; // 声明的变量如果没有进行赋值,或者没有被定义的变量,值默认是undefined 变量名 = 变量值; // 方式2 声明并赋值 var 变量名 = 变量值; // 方式3 一行可以声明多个变量.并且可
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摘要：<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title> <script> // 弹窗 // alert(123) </script> <script src="common.js"></scr
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摘要：第4章 、JavaScript 4.1、JavaScript 的历史 4.1.1、JavaScript 的历史 JavaScript 因为互联网而生，紧随着浏览器的出现而问世。回顾它的历史，就要从浏览器的历史讲起。 1990年底，欧洲核能研究组织（CERN）科学家Tim Berners-Lee，在全
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