描述：var a = {a: {b: {c: 1}, d: [1,2]}, e: 's'} 输出 [{key: 'abc', value: 1}, {key: 'ad', value: [1,2]}, {key: 'e', value: 's'}]

this is my answer

function getVal(obj,k="",arr=[]){
    for(var key in obj){
        if(Object.prototype.toString.call(obj[key]) === "[object Object]"&&obj[key]!==null){
           getVal(obj[key],k+key,arr)
        }else{
            arr.push({
                key:k+key,
                value:obj[key]
            })
        }
    }
    return arr;
}
getVal(a)

what's the better?

function getVal(obj, key = '') {
  return Object.entries(obj).map(item => {
    return Object.prototype.toString.call(item[1]) === '[object Object]'
      ? getVal(item[1], key + item[0])
      : { key: key + item[0], value: item[1] }
  }).flat()
}

也可以利用树的遍历。

function getVal(data) {
    // 非plain对象视为叶子节点
    if(Object.prototype.toString.call(data) !== '[object Object]') {
        return [{
            key: '',
            value: data
        }];
    }
    const result = [];
    Object.keys(data).forEach(key => {
        const childList = getVal(data[key]);
        childList.forEach(child => {
            child.key = key + child.key;
            result.push(child);
        })
    })
    return result;
}