学习nodejs必会基础预备知识
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学习nodejs必会基础预备知识
- 01-JavaScript 创建 JSON 对象 .html
- 02-JSON数据的数组访问.html
- 03-使用for in 循环访问对象.html
- 04-JSON嵌套对象.html
- 05-循环内嵌数组.html
- 06-使用 XMLHttpRequest 来获取JSON文件内容解析并显示.html
- 07-JavaScript 对象转换为 JSON 字符串.html
- 08-函数的自调用球.html
- 09-模块化编程.html
- 10-不改变原有模块代码的外部扩展.html
01-javascript 创建 JSON 对象 .html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>JavaScript 创建 JSON 对象 </title>
</head>
<body>
<h2>JavaScript 创建 JSON 对象</h2>
<p>
网站名称: <span id="jname"></span><br />
网站地址: <span id="jurl"></span><br />
网站 slogan: <span id="jslogan"></span><br />
</p>
</body>
<script>
var JSONobjet =
"name": '菜鸟教程',
"url": 'www.runoob.com',
"slogan": "学的不仅仅是梦想,更是梦想!"
;
document.getElementById('jname').innerHTML = JSONobjet.name;
document.getElementById('jurl').innerHTML = JSONobjet.url
document.getElementById('jslogan').innerHTML = JSONobjet.slogan
</script>
</html>
02-JSON数据的数组访问.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<h2>JavaScript 创建 JSON 对象</h2>
<p>第一个网站名称: <span id="name1"></span></p>
<p>第一个网站修改后的名称: <span id="name2"></span></p>
</body>
<script>
var sites = [
"name": "runoob", "url": "www.runoob.com" ,
"name": "google", "url": "www.google.com" ,
"name": "微博", "url": "www.weibo.com"
]
document.getElementById('name1').innerHTML = sites[0].name;
sites[0].name = '菜鸟教程';
document.getElementById('name2').innerHTML = sites[0].name;
</script>
</html>
03-使用for in 循环访问对象.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>使用forin循环访问对象</title>
</head>
<body>
<p>使用 for-in 来循环对象的属性:</p>
<p id="demo"></p>
</body>
<script>
var myobject =
"name": "runoob",
"alexa": 10000,
"site": null
;
for (x in myobject)
document.getElementById("demo").innerHTML += x + "<br/>"
</script>
</html>
04-JSON嵌套对象.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>JSON嵌套对象</title>
</head>
<body>
<p>访问 JSON 内嵌对象。</p>
<p id="demo"></p>
</body>
<script>
var myobject =
"name": "runoob",
"alexa": 1000,
"sites":
"site1": "www.bao.com",
"site2": ".cwww.cum.cn",
"site3": "c.runoob.com"
// 选中的是sites里面的第一个键值
document.getElementById("demo").innerHTML += myobject.sites.site1 + "<br/>";
//和：“.” 的用法一样，也就是说值Wie对象的的键值对也可以通过[]来获取
document.getElementById("demo").innerHTML += myobject.sites["site1"];
</script>
</html>
05-循环内嵌数组.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>循环内嵌数组</title>
</head>
<body>
<p>循环内嵌数组:</p>
<p id="demo"></p>
</body>
<script>
var i, j, x = '';
var obj =
"name": "网站",
"num": 3,
"sites": [
"name": "Google", "info": ["android", "Google 搜索", "Google 翻译"] ,
"name": "Runoob", "info": ["菜鸟教程", "菜鸟工具", "菜鸟微信"] ,
"name": "Taobao", "info": ["淘宝", "网购"]
]
for (i in obj.sites)
// console.log(i);
x += '<h1>' + obj.sites[i].name + '</h1>';
// console.log(x);
for (j in obj.sites[i].info)
x += obj.sites[i].info[j] + '<br/>';
document.getElementById('demo').innerHTML = x;
</script>
</html>
06-使用 XMLHttpRequest 来获取JSON文件内容解析并显示.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>使用 XMLHttpRequest 来获取JSON文件内容解析并显示</title>
</head>
<body>
<h2>使用XMLHttprequest来获取文件内容</h2>
<p>文件内容是标准的酒json格式,可以使用JSON.parse方法将其转为JavaScript对象</p>
<p id="demo"></p>
<p>查看JSON文件数据<a href="myjsion.json" target="_blank">myjsion.json</a></p>
</body>
<script>
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function ()
if (this.readyState == 4 && this.status == 200)
myobj = JSON.parse(this.responseText);
document.getElementById('demo').innerHTML = myobj.name;
;
xmlhttp.open('GET', "myjsion.json", true);
xmlhttp.send();
</script>
</html>
07-JavaScript 对象转换为 JSON 字符串.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>JavaScript 对象转换为 JSON 字符串</title>
</head>
<body>
<h2>将 JavaScript 对象转换为 JSON 字符串</h2>
<p id="demo"></p>
</body>
<script>
var obj = "name": "菜鸟", "alexa": 10000, "site": "www.runnob.com" ;
var myjson = JSON.stringify(obj);
document.getElementById('demo').innerHTML = myjson;
</script>
</html>
08-函数的自调用球.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>函数的自调用球</title>
</head>
<body>
请输入圆的半径:<input type="number" id="radius" name="radius">
<select id="type" name="type">
<option value="circu">周长</option>
<option value="area">面积</option>
<option value="volume">体积</option>
</select>
<input type="button" value=" 计 算 " id="btnCal">
</body>
<script>
function getCircu(r)
return 2 * Math.PI * r;
;
function getArea(r)
return Math.PI * Math.pow(r, 2);
;
function getTiji(r)
return 4 / 3 * Math.PI * Math.pow(r, 3);
;
document.getElementById('btnCal').onclick = function C++学习笔记—— 基础知识预备，以及“面向对象”的C++
求用python输入圆的半径，计算圆的周长和面积，结果保留2位小数的代码