1. 利用filter + indexof
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var intersection = arr1.filter(function (val) )
console.log(intersection); // [1, 3, 5]
2. 利用es6中 array.from方法及set
function intersect (a, b) ));
}var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var intersection = intersect (arr1, arr2);
console.log(intersection); // [1, 3, 5, nan]
3. 利用es7中陣列新增的includes + filter
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var intersection = arr1.filter(function (val) )
console.log(intersection); // [1, 3, 5, nan]
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var union= arr1.concat(arr2.filter(function (val) ))
console.log(union); // [1, 2, 3, 4, 5, 6, 7, 8, 9, nan, nan]
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var union= array.from(new set(arr1.concat(arr2)));
console.log(union); // [1, 2, 3, 4, 5, 6, 7, 8, 9, nan]
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var union= arr1.concat(arr2.filter(function (val) ));
console.log(union); // [1, 2, 3, 4, 5, 6, 7, 8, 9, nan]
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var difference = arr1.filter(function (val) ).concat(arr2.filter(function (val) ));
console.log(difference); // [2, 4, 6, 7, 8, 9, nan, nan]
function difference (a, b) )))
}var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var differenceval = difference (arr1, arr2);
console.log(differenceval ); // [2, 4, 6, 7, 8, 9]
var arr1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, nan], arr2 = [1, 3, 5, nan];
var difference = arr1.concat(arr2).filter(function (val) );
console.log(difference); // [2, 4, 6, 7, 8, 9]
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