vue学習のES 6_02(対象深度コピー、対象合併、mapとreduce)
1257 ワード
Study ES6
Hello ES6
//
let p1={name:'zs',age:26};
//
let someone={...p1};
writeLine(JSON.stringify(p1));
writeLine(JSON.stringify(p1));
//
let name1={name:'Alice'};
let age1={age:24};
let p2={...name1,...age1};
writeLine(JSON.stringify(p2));
//map(): ,
let arr=[4,20,12,13]
//reduce(): ,
arr=arr.map(item=>item+1);
writeLine(arr);
/* reduce */
/*
, ,
arr.reduce(callback,[initialValue])
callback :
1、previousValue ( , (initialValue))
2、currentValue ( )
3、index ( )
4、array ( reduce )
*/
let result=arr.reduce((a,b,index,d)=>{
writeLine(' '+a);
writeLine(' '+b);
writeLine(' '+index);
writeLine(' '+d);
return a+b;
});
writeLine(result);
//
function writeLine(s) {
document.write(s + "<br>")
}