如果子集数组中有值为null或0(零),则希望使用lodash从嵌套数组中删除数组项。我尝试了filter,但我正在寻找性能方面最好的方法。
const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
console.log("arr", arr);
// output should be [["a","b","c"],["d","e","f"]]
如果子集数组中有值为null或0(零),则希望使用lodash从嵌套数组中删除数组项。我尝试了filter,但我正在寻找性能方面最好的方法。
const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
console.log("arr", arr);
// output should be [["a","b","c"],["d","e","f"]]
filter()
和some()
函数。
const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
let res = arr.filter(x => !x.some(a => a === null || a === 0))
console.log(res)
lodash
库:使用filter
和includes
函数:const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
const result = _.filter(arr, x => !_.includes(x, null) && !_.includes(x, 0))
console.log(result)
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.14/lodash.min.js"></script>
ES6
: filter
和some
函数:const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
const result = arr.filter( x => !x.some(s => s === null || s === 0))
console.log(result)
ES6
: reduce
:const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
const result = arr.reduce( (acc, c) => {
if(c.some(x => x === null || x === 0)) {
return acc
}
return [...acc, c]
},[])
console.log(result)
filter()
和 some()
。""
和undefined
。const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"],["d",undefined,"f"],["d","e","f",""]];
var res = _.filter(arr, a => !a.some(i => !i));
console.log(res);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.14/lodash.core.min.js" integrity="sha256-NAQPwApfC7Ky1Y54LjXf7UrUQFbkmBEPFh/7F7Zbew4=" crossorigin="anonymous"></script>
使用原生JS:
const arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"],["d",undefined,"f"],["d","e","f",""]];
var res = arr.filter(a => !a.some(i => !i));
console.log(res);
//cost will not let modify the variable
let arr = [["a","b","c"],["f","r","p",0],["r",22,null,"t"],["d","e","f"]];
arr = arr.filter(aItem=>{
//compact will remove null, 0 , undefined values from array item
return aItem.length===_.compact(aItem).length;
});
console.log("...arr",arr);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.14/lodash.core.min.js"></script>