js递归（二）——合并多维数组

1.递归实现

 let [a,b,c] = [
        [1,2,3,[3,4,5,[5,6,7]]],
        ["a","b",["c","d",["aa","bb"]]],
        ["aaaa","bbbb"]
      ],
    //递归实现单个数组的多维转一维
     arrCat = a => a.reduce((p,c)=> p.concat(Array.isArray(c)?arrCat(c):c),[]),
    //es6扩展运算符
     arr= [...arrCat(a),...arrCat(b),...arrCat(c)]
    console.log(arr);
//[1, 2, 3, 3, 4, 5, 5, 6, 7, "a", "b", "c", "d", "aa", "bb", "aaaa", "bbbb"]

用forEach和reduce做一个简单的封装joinArr()函数显示数组的合并

let joinArr = (...arr)=> {
        let newArr = [];
        // [...arr].forEach(item=>{
        //     newArr.push(...arrCat(item))
        // })
        // return newArr
        return [...arr].reduce((p,c)=>{
            return p.concat(arrCat(c))
        },[])   
    }
console.log(joinArr(a, b, c));
//[1, 2, 3, 3, 4, 5, 5, 6, 7, "a", "b", "c", "d", "aa", "bb", "aaaa", "bbbb"]

2.补充

let [a,b,c] = [
        [1,2,3,[3,4,5,[5,6,7]]],
        ["a","b",["c","d",["aa","bb"]]],
        ["aaaa","bbbb"]
      ],
     k=[...a,...b,...c].toString().split(",");
    //字符串数字转成数字
     k=k.map(item=>{
        if (!isNaN(item-0)) return item-0
        return item
    })
    console.log(k);
//[1, 2, 3, 3, 4, 5, 5, 6, 7, "a", "b", "c", "d", "aa", "bb", "aaaa", "bbbb"]

完善：封装成joinArr()函数

 let [a,b,c] = [
            [1,2,3,[3,4,5,[5,6,7]]],
            ["a","b",["c","d",["aa","bb"]]],
            ["aaaa","bbbb"]
        ],
        joinArr = (...k) =>{
                let newArr =[...k].toString().split(",").map(item=>{
                    if (!isNaN(item-0)) return item-0
                    return item
                })
            return newArr
        }
    console.log(joinArr(a, b, c));