JS數組去重 ES6 方法
阿新 • • 發佈：2018-08-02
.so sort true index 數組排序 break [] rom array
let arr = [0, 0, 0, 0, 1, 2, 3, 4, 4, 5, 2, 3, 3, 3, 9, 8, 9];
//數組去重法1
console.log(Array.from(new Set(arr)));
//數組去重法2
console.log(...new Set(arr));
//數組去重法3 let newarr = []; for (var i = 0; i < arr.length; i++) { if (newarr.indexOf(arr[i]) == -1) { newarr.push(arr[i]); }; }; console.log(newarr); //數組去重法4 let newarr2 = []; arr.sort(); //先將數組排序 // newarr2.push(arr[0]); for (var i = 0; i < arr.length; i++) { if (arr[i] !== arr[i + 1]) { //判斷後一項 是否跟前一項一樣 將後一項放入新數組 newarr2.push(arr[i]); }; }; console.log(newarr2);
//數組去重 法5 var res = [arr[0]]; for (var i = 0; i < arr.length; i++) { var repeat = false; // console.log(res); for (var j = 0; j < res.length; j++) { if (arr[i] == res[j]) { repeat = true; break; } } if (!repeat) { res.push(arr[i]); } } console.log(res);
//數組去重 法6 var res = []; var json = {}; for (var i = 0; i < arr.length; i++) { if (!json[arr[i]]) { res.push(arr[i]); json[arr[i]] = 1; } } console.log(res);
//數組去重法3 let newarr = []; for (var i = 0; i < arr.length; i++) { if (newarr.indexOf(arr[i]) == -1) { newarr.push(arr[i]); }; }; console.log(newarr); //數組去重法4 let newarr2 = []; arr.sort(); //先將數組排序 // newarr2.push(arr[0]); for (var i = 0; i < arr.length; i++) { if (arr[i] !== arr[i + 1]) { //判斷後一項 是否跟前一項一樣 將後一項放入新數組 newarr2.push(arr[i]); }; }; console.log(newarr2);
//數組去重 法5 var res = [arr[0]]; for (var i = 0; i < arr.length; i++) { var repeat = false; // console.log(res); for (var j = 0; j < res.length; j++) { if (arr[i] == res[j]) { repeat = true; break; } } if (!repeat) { res.push(arr[i]); } } console.log(res);
//數組去重 法6 var res = []; var json = {}; for (var i = 0; i < arr.length; i++) { if (!json[arr[i]]) { res.push(arr[i]); json[arr[i]] = 1; } } console.log(res);
JS數組去重 ES6 方法