js根据数组对象中某个元素合并数组

一个数组，根据数组中某个元素，合并数组

// 需要被合并的数组,把Index相同的数组合并

const arr = [{id:0,name:'张三'}, {id:0,name:'李四'}, {id:1,name:'王五'}, {id:1,name:'张伟'}, {id:2,name:'张江'},  ] 

var map = {}, result = [];

for(var i = 0; i < arr.length; i++){
    var ai = arr[i];
    if(!map[ai.id]){
        result.push({
            id: ai.id,
            name: ai.name,
            data: [ai]
        });
        map[ai.id] = ai;
    }else{
        for(var j = 0; j < result.length; j++){
            var dj = result[j];
            if(dj.id == ai.id){
                dj.data.push(ai);
                break;
            }
        }
    }
}

console.log(result)

//
[{"id":0,"name":"张三","data":[{"id":0,"name":"张三"},{"id":0,"name":"李四"}]},
{"id":1,"name":"王五","data":[{"id":1,"name":"王五"},{"id":1,"name":"张伟"}]},
{"id":2,"name":"张江","data":[{"id":2,"name":"张江"}]}]