<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Math</title>
<script type="text/javascript">
// var num = Math.random();
// alert(num);//弹出0-1之间的随机数
var a = 1;
var b = 17;
// var num = Math.random()*(b-a)+a;
// alert(num);//弹出10-20之间的随机数
var arr = [];
for(var i=0; i<20; i++){
// var num = Math.floor(Math.random()*(b-a)+a);//向下取整，10-19
var num = Math.floor(Math.random()*(b-a + 1)+a);//向下取整，10-20
arr.push(num);//生成一个数就放进数组
}
alert(arr);//17,20,20,11,11,19,17,16,10,11,16,11,18,13,13,11,17,14,19,19
</script>
</head>
<body>
</body>
</html>
单体创建对象：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>单体创建对象</title>
<script type="text/javascript">
var Tom = {
// 属性
name:'tom',
age:18,
// 方法
showName:function(){
alert(this.name);
},
showAge:function(){
alert(this.age);
}
}
//调用属性
alert(Tom.name);
alert(Tom.age);
//调用方法
Tom.showName();
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>单体创建对象</title>
<script type="text/javascript">
var Tom = {
// 属性
name:'tom',
age:18,
// 方法
showName:function(){
alert(this.name);
},
showAge:function(){
alert(this.age);
}
}
//调用属性
alert(Tom.name);
alert(Tom.age);
//调用方法
Tom.showName();
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>工厂模式创建对象</title>
<script type="text/javascript">
function Person(name,age,job){
//创建一个空对象
// var o = new Object();//方式一
var o = {};//方式二
o.name = name;
o.age = age;
o.job = job;
o.showName = function(){
alert(this.name);
}
o.showAge = function(){
alert(this.age);
}
o.showJob = function(){
alert(this.job);
}
return o;
}
var Tom = Person('tom',18,'程序猿');
Tom.showJob();
var Jack = Person('jack',19,'攻城狮');
Jack.showJob();
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>构造函数</title>
<script type="text/javascript">
function Person(name,age,job){
this.name = name;
this.age = age;
this.job = job;
this.showName = function(){
alert(this.name);
}
this.showAge = function(){
alert(this.age);
}
this.showJob = function(){
alert(this.job);
}
}
//new的作用就相当于工厂模式中最开始创建了一个空对象，最后把对象返回
var Bob = new Person('bob',18,'产品汪');
Bob.showJob();
var Alex = new Person('alex',19,'运营喵');
Alex.showJob();
alert(Bob.showName == Alex.showName);//false
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>原型模式</title>
<script type="text/javascript">
function Person(name,age,job){
this.name = name;
this.age = age;
this.job = job;
Person.prototype.showName = function(){
alert(this.name);
}
Person.prototype.showAge = function(){
alert(this.age);
}
Person.prototype.showJob = function(){
alert(this.job);
}
}
//先去自己的对象中找showName函数，再去构造函数的原型找
var Lucy = new Person('lucy',18,'测试鼠');
//重写自身对象中的方法，不会影响其它对象
Lucy.showName = function(){
alert('我的名字是' + this.name);
}
Lucy.showName();//我的名字是lucy
var Lily = new Person('lily',19,'市场鸡');
Lily.showName();//lily
alert(Lucy.showName == Lily.showName);//false
</script>
</head>
<body>
</body>
</html>
call和apply
<script type="text/javascript">
/* call和apply的区别
二者都可以改变当前的this，区别在于apply方法要将参数放入数组中再传参*/
function aa(a,b){
alert('我的this是' + this + ',我的a是' + a + ',我的b是' + b);
}
aa(2,3);
aa.call('abc',2,3);//我的this是abc,我的a是2,我的b是3
aa.apply('abc',[2,3])
call和apply都可以调用函数，可以用修改this
传参方式不同 call方法将参数直接放在 apply方法要将参数放入数组中再传参
</script>
函数的继承
<script type="text/javascript">
//父类
function Fclass(name, age){
this.name = name;
this.age = age;
}
Fclass.prototype.showName = function(){
alert(this.name);
}
Fclass.prototype.showAge = function(){
alert(this.age);
}
//子类
function Sclass(name, age, job){
//调用父类的call方法实现属性的继承
this.job = job;
}
//方法的继承 (父类的实例赋给子类的原型)
Sclass.prototype = new Fclass();
Sclass.prototype.showJob = function(){
alert(this.job);
};
var Driver = new Sclass('tom',18,'老司机')//创建一个子类的实例//
Driver.showJob();
Driver.showAge();
Driver.showName();
</script>
新增选择器
<script type="text/javascript">
window.onload = function(){
var div1 = document.querySelector('#div1');
console.log(div1);
var lis = document.querySelectorAll('.list li');
console.log(lis.length);//8
}
<div id="div1">这是一个div元素</div>
<ul class="list">
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
<li>5</li>
<li>6</li>
<li>7</li>
<li>8</li>
</ul>
</script>
