前面的话
前面的博文中介绍了对象拷贝,本文将详细介绍数组复制
push
function copyArray(arr){
var result = [];
for(var i = 0; i < arr.length; i++){
result.push(arr[i]);
}
return result;
}
var obj1=[1,2,3];
var obj2=copyArray(obj1);
console.log(obj1); //[1,2,3]
console.log(obj2); //[1,2,3]
obj2.push(4);
console.log(obj1); //[1,2,3]
console.log(obj2); //[1,2,3,4]
立即学习“Java免费学习笔记(深入)”;
join
使用该方法的缺点是数组中的项全部变成了字符串形式
function copyArray(arr){
var result = [];
result = arr.join().split(',');
return result;
}
var obj1=[1,2,3];
var obj2=copyArray(obj1);
console.log(obj1); //[1,2,3]
console.log(obj2); //['1','2','3']
obj2.push(4);
console.log(obj1); //[1,2,3]
console.log(obj2); //['1','2','3',4]
立即学习“Java免费学习笔记(深入)”;
concat
function copyArray(arr){
var result = [];
result = arr.concat();
return result;
}
var obj1=[1,2,3];
var obj2=copyArray(obj1);
console.log(obj1); //[1,2,3]
console.log(obj2); //[1,2,3]
obj2.push(4);
console.log(obj1); //[1,2,3]
console.log(obj2); //[1,2,3,4]
立即学习“Java免费学习笔记(深入)”;
slice
function copyArray(arr){
var result = [];
result = arr.slice();
return result;
}
var obj1=[1,2,3];
var obj2=copyArray(obj1);
console.log(obj1); //[1,2,3]
console.log(obj2); //[1,2,3]
obj2.push(4);
console.log(obj1); //[1,2,3]
console.log(obj2); //[1,2,3,4]
立即学习“Java免费学习笔记(深入)”;
深拷贝
以上方法实现的仅是数组的浅拷贝,如果要实现数组的深拷贝,需要使用递归方法
function copyArray(arr,result){
var result = result || [];
for(var i = 0; i < arr.length; i++){
if(arr[i] instanceof Array){
result[i] = [];
copyArray(arr[i],result[i]);
}else{
result[i] = arr[i];
}
}
return result;
}
var obj1=[1,2,[3,4]];
var obj2=copyArray(obj1);
console.log(obj1[2]); //[3,4]
console.log(obj2[2]); //[3,4]
obj2[2].push(5);
console.log(obj1[2]); //[3,4]
console.log(obj2[2]); //[3,4,5]更多JavaScript数组复制详解相关文章请关注PHP中文网!
立即学习“Java免费学习笔记(深入)”;
java怎么学习?java怎么入门?java在哪学?java怎么学才快?不用担心,这里为大家提供了java速学教程(入门到精通),有需要的小伙伴保存下载就能学习啦!
Copyright 2014-2025 https://www.php.cn/ All Rights Reserved | php.cn | 湘ICP备2023035733号