内置date
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>date定义和体验</title>
</head>
<body>
<script>
//第一种获取当前时间
var date1=new Date();
console.log(date1);
//第二种指定事件
var date2=new Date("2016/09/06 00:00:01");
console.log(date2);
console.log(date1.getDate()); //获取日 1-31
console.log(date1.getDay()); //获取星期--6(0代表周日)
console.log(date1.getMonth()); //获取月0-11(1月从0开始)
console.log(date1.getFullYear()); //获取完整的年份()
console.log(date1.getHours()); //获取小时0-23
console.log(date1.getMinutes()); //获取分钟0-59
console.log(date1.getSeconds()); //获取秒(0-59)
console.log(date1.getMilliseconds()); //获取毫秒(1s=1000ms)
console.log(date1.getTime()); //返回累计毫秒数(从1970/1/1)
</script>
</body>
</html>
string
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>string</title>
</head>
<body>
<script>
// var str = new String("abcd");
//charAt
// for(var i=0;i<str.length;i++){
// console.log(str.charAt(i));
// }
//charCodeAt asci码
// console.log(str.charCodeAt(0));
//给字符查索引,索引值为0,说明字符串以传输的参数为开头
// console.log(str.indexOf("c"));
// console.log(str.lastIndexOf("c"));
//uri解析
// var url="http://www.baidu.com/test?user=zk&pwd=123";
// console.log(encodeURIComponent(url));
// console.log(decodeURIComponent(encodeURIComponent(url)))
//字符串连接和截取
// var str1="abc";
// var str2="123";
// var str3 = str1.concat(str2);
// console.log(str3)
var str="I love my family";
//slice()
// console.log(str.slice(2)); //从索引截取到最后
// console.log(str.slice(2,6));//截取2-6的字符,包左不包右
// console.log(str.slice(-3));//截取后3个
// console.log(str.slice(5,2));//空字符
//substr() 根据索引值数字截取字符
// console.log(str.substr(2)); //从索引截取到最后
// console.log(str.substr(2,6));//从索引截取,长度为6的字符串
// console.log(str.substr(-3));//截取后3个
//substring
console.log(str.substring(2)); //从索引截取到最后
console.log(str.substring(2,5));//截取2-6的字符,包左不包右
console.log(str.substring(-3));//全部字符串
console.log(str.substring(5,2));//只能调换
//特殊方法
//去除前后空格trim()
// var str1=" a 2 3 ";
// console.log(str1);
// console.log(str1.trim());
//替换 replace()只能替换一个
// var str2="today is find day,today is find day a !!!";
// console.log(str2);
// console.log(str2.replace(/today/g,"tomorrow"));
//字符串变数组
// var str3="关羽|张飞|刘备";
// console.log(str3);
// console.log(str3.split("|"));
// var str4="ABCDefG";
// //转换成小写
// console.log(str4.toLowerCase());
// //转换成大写
// console.log(str4.toUpperCase());
var str5="abccdssfasdfasdfafasddfa";
var json={};
for(var i=0;i<str5.length;i++){
var key=str5.charAt(i);
if(json[key] === undefined){
json[key] = 1;
}else{
json[key]+=1;
}
}
var maxkey="";
var maxValue=0;
for(var k in json){
if(json[k] >maxValue){
maxkey=k;
maxValue=json[k];
}
}
console.log(maxkey);
console.log(maxValue);
// console.log(json);
</script>
</body>
</html>
获取元素节点的封装
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>获取节点元素的封装</title>
<style>
div{
100px;
height: 100px;
background-color: pink;
margin: 5px;
}
</style>
</head>
<body>
<div></div>
<div class="box"></div>
<div id="box"></div>
<div class="box"></div>
<script>
//一个方法包含三种获取元素节点的功能,通过传递参数的不通决定用什么方式获取
getEle("#box").style.backgroundColor = "red";
// var divArr=getEle(".box")[0].style.backgroundColor="red";
var claArr=getEle(".box");
for(var i=0;i<claArr.length;i++){
claArr[i].style.backgroundColor = "yellow";
}
var divArr=getEle("div");
for(var i=0;i<divArr.length;i++){
divArr[i].style.border = "2px solid #000";
}
//#box getElementById()
//.box getElementsByClassName()
// div getElementsByTagName()
function getEle(str) {
var str1=str.charAt(0);
if(str1 === "#"){
return document.getElementById(str.slice(1));
}else if(str1 === "."){
return document.getElementsByClassName(str.slice(1));
}else{
return document.getElementsByTagName(str);
}
}
</script>
</body>
</html>
获取元素节点的封装(终极版$)
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>获取节点元素的封装(最终)</title>
<style>
div{
100px;
height: 100px;
background-color: pink;
margin: 5px;
}
</style>
</head>
<body>
<div></div>
<div class="box"></div>
<div id="box"></div>
<div class="box"></div>
<script>
//一个方法包含三种获取元素节点的功能,通过传递参数的不通决定用什么方式获取
$("#box").style.backgroundColor = "red";
// var divArr=getEle(".box")[0].style.backgroundColor="red";
var claArr=$(".box");
for(var i=0;i<claArr.length;i++){
claArr[i].style.backgroundColor = "yellow";
}
var divArr=$("div");
for(var i=0;i<divArr.length;i++){
divArr[i].style.border = "2px solid #000";
}
//#box getElementById()
//.box getElementsByClassName()
// div getElementsByTagName()
function $(str) {
var str1=str.charAt(0);
if(str1 === "#"){
return document.getElementById(str.slice(1));
}else if(str1 === "."){
return document.getElementsByClassName(str.slice(1));
}else{
return document.getElementsByTagName(str);
}
}
</script>
</body>
</html>
事件概述
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>获取节点元素的封装(最终)</title>
<style>
div{
100px;
height: 100px;
background-color: pink;
margin: 5px;
}
</style>
</head>
<body>
<div></div>
<div class="box"></div>
<div id="box"></div>
<div class="box"></div>
<script>
//一个方法包含三种获取元素节点的功能,通过传递参数的不通决定用什么方式获取
$("#box").style.backgroundColor = "red";
// var divArr=getEle(".box")[0].style.backgroundColor="red";
var claArr=$(".box");
for(var i=0;i<claArr.length;i++){
claArr[i].style.backgroundColor = "yellow";
}
var divArr=$("div");
for(var i=0;i<divArr.length;i++){
divArr[i].style.border = "2px solid #000";
}
//#box getElementById()
//.box getElementsByClassName()
// div getElementsByTagName()
function $(str) {
var str1=str.charAt(0);
if(str1 === "#"){
return document.getElementById(str.slice(1));
}else if(str1 === "."){
return document.getElementsByClassName(str.slice(1));
}else{
return document.getElementsByTagName(str);
}
}
</script>
</body>
</html>
事件绑定/取消绑定兼容写法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
</body>
</html><!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>事件概述</title>
</head>
<body>
<button>赋诗</button>
<script>
var btn = document.getElementsByTagName("button")[0];
// btn.addEventListener("click",fn1);
// btn.addEventListener("click",fn2);
function fn1() {
console.log("床前明月光,疑是地上霜");
}
function fn2() {
console.log("抬头望明月,低头思故乡");
}
function fn3() {
console.log("抬头望明月,低头思故乡");
}
fn("click",fn1,btn);
fn("click",fn2,btn);
fn("click",fn3,btn);
EventListen = {
//判断是否兼容IE678
addEvent:function (ele,fn,str) {
if(ele.addEventListener){
ele.addEventListener(str,fn);
}else if(ele.attachEvent){
ele.attachEvent("on"+str,fn);
}else{
ele["on"+str]=fn;
}
}
}
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
</body>
</html><!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>事件概述</title>
</head>
<body>
<button>赋诗</button>
<script>
var btn = document.getElementsByTagName("button")[0];
EventListen ={
removeEvent:function (ele,fn,str) {
if(ele.removeEventListener){
console.log("OK");
ele.removeEventListener(str,fn);
}else if(ele.detachEvent){
ele.detachEvent("on"+str,fn);
}else{
ele["on"+str]= null;
}
}
};
// btn.onclick=fn;
btn.addEventListener("click",fn);
EventListen.removeEvent(btn,fn,"click");
function fn() {
alert(1)
}
// //第一种解绑方式
// btn.onclick=function () {
// alert(1);
// };
// // btn.onclick = null;
// //第二种
// btn.addEventListener("click",fn);
// function fn() {
// alert(1)
// }
// btn.removeEventListener("click",fn);
// btn.attachEvent("onclick",fn);
// function fn() {
// alert(1);
// }
// btn.detachEvent("onclick",fn);
</script>
</body>
</html>