利用treegrid的loadFilter显示列的子属性

tree的node：
{
    id：1，text：'aaa', attr:{m0:'xxx',m1:'yyy'}
}
子属性attr.m0,attr.m1显示为两列

$('#treeid').treegrid({
    columns:[[
           {field:"text",title:'单位名称'},
          *{field:"m0",title:'收费'},
           {field:"m1",title:'监控'}
    ]],
    loadFilter:function(data,parentId){
        for(var i=0;i<data.length;i++){
            var row = data[i];
            if(row.attr){
                var attr = row.attr;
                for(var j=0; j<=10; j++){
                    row["m"+j] = attr["m"+j];
                }
                row.attr = undefined;
            }
        }
        return data;
    }