分享两个偶尔能用的js函数数组去重和数组降维

js数组去重

var a = [1, 2, 3, 3, 3, 4, 5, 1, 2, 3, 2, 4, 5];  function quchong(x) {//去重    let res = [];    for (let i = 0; i < x.length; i++) {      if (res.indexOf(x[i]) == -1) {        res.push(x[i]);      }    }    return res;  }//结果 [1,2,3,4,5]

js数组降维

var b = [1, 2, 3, [4, 5, 6, [7, 8, 9]]];  function jiangwei(x) {//数组降维    let res = [];    for (let i = 0; i < x.length; i++) {      if (Array.isArray(x[i])) {        let _r = jiangwei(x[i]);        for (let j = 0; j < _r.length; j++) {          res.push(_r[j]);        }      } else {        res.push(x[i]);      }    }    return res;  }//结果 [1,2,3,4,5,6,7,8,9]