JS的一些简单实例用法

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../javascript/OutSideJs.js"></script>
    <style>
        .myStyle{
            background-color: red;
            500px;
            height: 500px;
            border: 1px solid;
        }
    </style>
    <script>
//        alert(width);//输出信息
        var height = 200;
        function test() {
            alert(width);
        }
        function test1() {
            alert(height);
        }
        //document.write 打印指定的文本内容到页面上
        function load(count,str) {
            for (var i = 0; i < count; i++) {
                document.write("<h1>"+str+"</h1>")
            }
            //prompt 输出一个输入框(让你输入东西)
            var s= prompt("提示信息","输入框的默认信息");
            document.write("<h2>"+s+"</h2>")
        }
        function cleanValue(obj) {
            obj.value="";
        }
        function getValue(obj) {
           var a=obj.value;
            if (a!="") {
                alert(a.length);//长度
                alert(a.substring(0,1));//截取
                try{

                }catch (e){
                    e.message;
                }finally {

                }
                //split分割字符串
                var strs=a.split(",");//分割字符串
                for (var i=0;i<strs.length;i++){
                    alert(strs[i]);
                }
            }
        }
        function checkUser() {
            //document 根据文档找元素
            var name=document.getElementById("name");
            var pwd=document.getElementById("pwd");
            alert("用户名:"+name.value+" "+"密码:"+pwd.value);
        }
        //获取Json数据
        var text = '{"employees":[' +
        '{"firstName":"John","lastName":"Doe" },' +
        '{"firstName":"Anna","lastName":"Smith" },' +
        '{"firstName":"Peter","lastName":"Jones" }]}';
        //parse()方法的作用是:解析
        function getJson() {
            var obj=JSON.parse(text);
            alert(obj.employees[0].firstName+" "+obj.employees[0].lastName);
        }
        //获取日期
        function getDate() {
            var date=new Date();
            alert(date);
        }
        //对话框
        function getdel() {
            //confirm()弹出确认框(确定  取消)
            var s=confirm("您确定要删除吗?")
            if (s){
                alert("删除成功");
            }else {
                alert("已取消");
            }
        }
        //定时的函数,每隔一秒就运行一次  setInterval 动作的作用是在播放动画时,每隔一定的时间就调用函数 或方法 或对象
        var id= window.setInterval(function () {
            var obj=document.getElementById("time");
            obj.value=new Date().getMinutes()+":"+new Date().getSeconds()
        },1000);
       //设定一个时间  时间到了就执行指定的方法
        window.setTimeout(function () {
            //clearInterval()方法取消setInterval()方法设置的定时器
            window.clearInterval(id);
            window.close();
        },10000);
        //打开新窗口
        function getopenWindow() {
            window.open("http://www.baidu.com","我的百度",400,500);
        }
        //关闭窗口
        function getcloseWindow() {
            window.close();
        }
        //获取屏幕的高度和宽度
        function getWindowHeight() {
            alert(screen.availHeight);
            alert(screen.height);
            alert(screen.availWidth);
            alert(screen.width);
        }
        function setCookie() {
            var d=new Date();
            document.cookie="King"+":"+d.getDay();
            var expires = "expires="+d.toGMTString();
            document.cookie = cname + "=" + cvalue + "; " + expires;

        }
        function getCookie() {
            var str=document.cookie;
            alert(str);
        }
        function getBackgroundColor() {
           var div1=document.getElementById("div1");
//            div1.style.backgroundColor="red";
              div1.className="myStyle";//???????不好使
//            div1.innerText="King&Queen"  //插入内部文本
            div1.innerHTML="<h1>HTML</h1>"//插入HTML
        }
        //增加行数
        function addrow() {
            var tab1=document.getElementById("tab1")
            var row=tab1.insertRow();
            var c1=row.insertCell(0);
            var c2=row.insertCell(1);
            var c3=row.insertCell(2);
            c1.innerText="a";
            c2.innerText="b";
            c3.innerText="c";
        }
        //获取X Y的坐标
        function getXY(event) {
            alert(event.clientX+":"+event.clientY);
        }
        //删除元素
        function deleteTable() {
            var tab1=document.getElementById("tab1");
            document.body.removeChild(tab1);
        }
        //下拉列表
        function getItem(obj) {
            alert(obj.value);
        }
        //跳转画面
        function go() {
//  第一种方法          window.location.href="边走边乔.html";
            window.open("边走边乔.html","","0,0,1200,1200")
        }
    </script>
</head>
<body>
   <h1 ondblclick="load(10,'hello King')">点击我</h1>
    <input type="text" onfocus="cleanValue(this)" onblur="getValue(this)" value="我是输入框">
    <input type="text" id="time">
   用户名:<input type="text" id="name">
    密码:<input type="password" id="pwd">
    <input type="button" value="测试" onclick="checkUser()">
    <input type="button" value="Json" onclick="getJson()">
    <input type="button" value="获取日期" onclick="getDate()">
    <input type="button" value="对话框" onclick="getdel()">
    <input type="button" value="打开新窗口" onclick="getopenWindow()">
    <input type="button" value="关闭新窗口" onclick="getcloseWindow()">
    <input type="button" value="屏幕的尺寸" onclick="getWindowHeight()">
    <input type="button" value="设置Cookie" onclick="setCookie()">
    <input type="button" value="读取Cookie" onclick="getCookie()">
    <input type="button" value="改变DIV背景色" onclick="getBackgroundColor()">
    <input type="button" value="增加行数" onclick="addrow()">
    <input type="button" value="删除table" onclick="deleteTable()">
    <input type="button" value="跳转" onclick="go()">
    <div id="div1" style=" 200px;height: 200px;"></div>
    <table id="tab1" style="border: 1px solid red; 300px;">
        <tr style="border: 1px solid black">
            <td width="100px">1</td>
            <td width="100px">2</td>
            <td width="100px">3</td>
        </tr>
        <tr>
            <td width="100px">1</td>
            <td width="100px">2</td>
            <td width="100px">3</td>
        </tr>
        <tr>
            <td width="100px">1</td>
            <td width="100px">2</td>
            <td width="100px">3</td>
        </tr>
    </table>
    <select style=" 100px;height: auto" onchange="getItem(this)">
       <option value="0">--请选择--</option>
       <option value="1">江西省</option>
       <option value="2">山东省</option>
       <option value="3">福建省</option>
</select>
</body>
</html>

原文地址:https://www.cnblogs.com/Dionexin/p/5980411.html