數據類型的拷貝

//淺拷貝
var a={a:18}; var b=a; b.m=22 console.log(a) {a: 18, m: 22} console.log(b) {a: 18, m: 22}  

//深拷貝
var c=JSON.stringify(a) console.log(c) // {"a":18,"m":22}
Object.prototype.toString.call(c) "[object String]"

var d=JSON.parse(c) Object.prototype.toString.call(d) "[object Object]" d.e=88 console.log(a) {a: 18, m: 22} console.log(d) {a: 18, m: 22, e: 88}