JS遍历子孙树

function fn(dataList,parent_id){

    var result = [] , temp;

    for(var i in dataList){

        if(dataList[i].parent_id==parent_id){

            result.push(dataList[i]);

            temp = fn(dataList,dataList[i].key);           

            if(temp.length>0){

dataList[i].children=temp;

            }           

        }       

    }

    return result;

}

const treeData =fn(dataList,-1);

 

dataList：取出来的所有数据

-1：最顶层的parent的id