对象字符串转化成树形结构 about js-challenges HOT 3 OPEN

let strarr = {  
  'a-b-c-d':1,  
  'a-b-c-e':2,  
  'a-b-f':3,  
  'a-j':4  
} 
const data = Object.keys(strarr).reduce(function (acc, cur) {
  const _keys = cur.split('-');
  let tmp = acc;
  _keys.forEach((key, idx) => {
    if (idx === _keys.length - 1) {
      tmp[key] = strarr[cur];
    } else {
      if (!tmp[key]) tmp[key] = {};
      tmp = tmp[key];
    }
  });
  return acc;
}, {});

function strToTree(strArr){
  let objTree = {}
  const dfs = (arr,obj,val) => {
    for(let i=0; i<arr.length-1; i++){
      if(!obj[arr[i]]) obj[arr[i]] = {}
      obj = obj[arr[i]]
    }
    obj[arr[arr.length-1]] = val
  }
  for(let str in strArr){
    dfs(str.split('-'),objTree,strArr[str])
  }
  return objTree
}

console.log(strToTree(strArr))

function strObjtoTree(strarr) {
    let obj = {};

    for (let key in strarr) {
        let propertyNames = key.split('-');
        let lastPropertyName = propertyNames.pop();
        let nestedObj = obj;
        for (let propertyName of propertyNames) {
            nestedObj[propertyName] = nestedObj[propertyName] || {};
            nestedObj = nestedObj[propertyName];
        }
        nestedObj[lastPropertyName] = strarr[key];
    }
    return obj
}

function convertToObject(strarr) {
  const result = {};
  for (let key in strarr) {
    const keys = key.split('-');
    let obj = result;
    for (let i = 0; i < keys.length - 1; i++) {
      const k = keys[i];
      obj[k] = obj[k] || {};
      obj = obj[k];
    }
    obj[keys[keys.length - 1]] = strarr[key];
  }
  return result;
}