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]
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]
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]
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]
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]
您可能感兴趣的文章: