JavaScript笔记-解构赋值
https://www.liaoxuefeng.com/wiki/1022910821149312基于廖雪峰老师的教程所做的笔记。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>解构赋值操作展示</title>
</head>
<body>
<script>
/*解构赋值*/
/*解构数组*/
console.log("解构数组：");
var [a,b,c]=["我是a","我是b","我是c"];//var [v1,v2,...]=[c1,c2,...]
console.log(a);
console.log(b);
console.log(c);
var [d,e,f]=[,,"我是f"];//前两个不赋值，最后一个赋值
console.log(d);
console.log(e);
console.log(f);
/*解构对象*/
/*一般的对象*/
console.log("解构一般对象：");
var obj={
name:"Sang",
age:20,
city:"Guoyang"
};
var {name,age,city}=obj;//var {属性1,属性2,...}=对象
console.log(name);
console.log(age);
console.log(city);
/*含有对象的对象*/
console.log("解构含有对象的对象：")
var person={
lastName:"Sang",
address:{
city:"Guoyang",
town:"Chengxi"
}
}
var {lastName,address:{city,town}}=person;//这里address不是变量，只是通过它给city,town赋值而已
console.log(lastName);
console.log(city);
console.log(town);
/*解构赋值的使用小技巧*/
/*变量迅速交换*/
console.log("变量交换：")
var x=1,y=2;
[x,y]=[y,x];
console.log(x);
console.log(y);
/*获取当前页面域名、路径*/
console.log("获取当前页面域名、路径：")
var{hostname:domain,pathname:path}=location;
console.log(domain);
console.log(path);
/*函数传入对象*/
function display({lastname,firstname="Guorui"}){
console.log(lastname+firstname);
}
display({lastname:"Sang"});
display({lastname:"Sang",firstname:"haha"});
</script>
</body>
</html>
