1.使用ES6 新增的擴展運算符和Set新數據類型判斷兩個數組是否包含有相同的元素
var arr1 = ['green' , 'yellow' ,'blue' ,'red']; var arr2 = ['lightlue' , 'red' , 'pink']; var arr3 = ['yellow' ,'blue' ,'red', 'green']; arr1.push(...arr2); var arrset1 = new Set(arr1); if([...arrset1].length == arr2.length){ alert("arr1和arr2兩個數組相等"); }else{ alert('arr1 和arr2 兩個數組不相等'); }