标签：取数 扩展运算 返回 port UNC title 浅拷贝 连接 script
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>数组的深拷贝与浅拷贝</title>
</head>
<body>
<script>
//数组的浅拷贝
var arr1= [1,23,5,1,3];
var arr2 = arr1;
arr1[0] = 99;
console.log(arr1[0]);
console.log(arr2[0]);
console.log(arr1);
console.log(arr2);
//数组的深拷贝
var arr3 = arr1.concat(); //连接数组，如果连接的是一个空，那么也是返回了新的本身的数组
console.log(arr3);
arr1[0]= 100;
console.log("arr1: "+arr1[0]);
console.log("arr3: "+arr3[0]);
console.log("arr1: "+arr1);
console.log("arr3: "+arr3);
var arr4 = arr1.slice(0); //从0开始到末尾截取数组，然后返回一个新的数组
arr1[0]= 88;
console.log("arr1: "+arr1[0]);
console.log("arr4: "+arr4[0]);
console.log("arr1: "+arr1);
console.log("arr4: "+arr4);
var arr5 = arr1.map(function(value){ //使用map方法遍历数组然后返回新的数组，里面的值不变
return value;
})
arr1[0]= 77;
console.log("arr1: "+arr1[0]);
console.log("arr5: "+arr5[0]);
console.log("arr1: "+arr1);
console.log("arr5: "+arr5);
var [...arr6] = arr1//ES6扩展运算符实现数组的深拷贝
arr1[0]= 66;
console.log("arr1: "+arr1[0]);
console.log("arr6: "+arr6[0]);
console.log("arr1: "+arr1);
console.log("arr6: "+arr6);
</script>
</body>
</html>
标签：取数 扩展运算 返回 port UNC title 浅拷贝 连接 script
原文地址：https://www.cnblogs.com/shine1234/p/12986471.html
