我正在使用node和express并在JSON中向前端发送值 形式如
[
{
"id": "1",
"name": "Plant Director",
"parentJobID": -1,
"children": [
{
"id": "19",
"name": "Operations Director",
"parentJobID": 1,
"children": [
{
"id": "16",
"name": "Financial planning and costs Manager",
"parentJobID": 19,
"children": [
{
"id": "14",
"name": "Cost Analyst",
"parentJobID": 16,
"children": []
},
{
"id": "15",
"name": "Head of Costs",
"parentJobID": 16,
"children": []
}
]
},
{
"id": "17",
"name": "Manufacturing Manager",
"parentJobID": 19,
"children": [
{
"id": "2",
"name": "Head of Security",
"parentJobID": 17,
"children": [
{
"id": "3",
"name": "Asistente Ejecutiva",
"parentJobID": 2,
"children": []
},
{
"id": "8",
"name": "Jefe de Mantenimiento",
"parentJobID": 2,
"children": []
},
{
"id": "27",
"name": "Jefe Aseguramiento de Calidad",
"parentJobID": 2,
"children": [
{
"id": "28",
"name": "Jefe Seguridad Alimentaria",
"parentJobID": 27,
"children": [
{
"id": "33",
"name": "Operario Fabricación A (2)",
"parentJobID": 28,
"children": []
},
{
"id": "34",
"name": "Operario Fabricación B (2)",
"parentJobID": 28,
"children": []
}
]
},
{
"id": "29",
"name": "Especialista Aseguramiento de Calidad",
"parentJobID": 27,
"children": []
},
{
"id": "30",
"name": "Especialista en Microbiología",
"parentJobID": 27,
"children": []
},
{
"id": "31",
"name": "Especialista en Evaluación Sensorial",
"parentJobID": 27,
"children": []
},
{
"id": "32",
"name": "Técnico Aseguramiento de Calidad",
"parentJobID": 27,
"children": []
}
]
}
]
},
{
"id": "4",
"name": "Production Manager",
"parentJobID": 17,
"children": []
},
{
"id": "5",
"name": "Head of Maintenance",
"parentJobID": 17,
"children": []
},
{
"id": "6",
"name": "Quality Control Manager",
"parentJobID": 17,
"children": [
{
"id": "7",
"name": "Técnico Medio Ambiente",
"parentJobID": 6,
"children": []
},
{
"id": "23",
"name": "Quality Control Technician 1",
"parentJobID": 6,
"children": [
{
"id": "25",
"name": "Operario Fabricación B",
"parentJobID": 23,
"children": []
},
{
"id": "26",
"name": "Operario Fabricación D",
"parentJobID": 23,
"children": []
}
]
},
{
"id": "24",
"name": "Quality Control Technician 2",
"parentJobID": 6,
"children": []
}
]
},
{
"id": "9",
"name": "Warehouse Manager",
"parentJobID": 17,
"children": []
},
{
"id": "10",
"name": "Head of Planning",
"parentJobID": 17,
"children": [
{
"id": "20",
"name": "Operario Mtto A (2)",
"parentJobID": 10,
"children": []
}
]
},
{
"id": "11",
"name": "Head of Continuous Improvement",
"parentJobID": 17,
"children": [
{
"id": "21",
"name": "Operario Servicios A (2)",
"parentJobID": 11,
"children": []
}
]
},
{
"id": "12",
"name": "Head of Supplies",
"parentJobID": 17,
"children": []
},
{
"id": "13",
"name": "Process Manager",
"parentJobID": 17,
"children": []
},
{
"id": "18",
"name": "IT Manager",
"parentJobID": 17,
"children": []
}
]
}
]
},
{
"id": "35",
"name": "[ LINEA DE PRODUCCION ]",
"parentJobID": 1,
"children": []
}
]
},
{
"id": "22",
"name": "Extrusion Area",
"parentJobID": -1,
"children": []
}
]
在前端调用一个函数来创建层次结构
<script>
function sim(list)
{
for (var i = 0; i < list.length; i++) {
var li = document.createElement('li');
li.innerHTML = list[i].name;
if (list[i].children.length > 0) {
var ul = document.createElement('ul');
li.appendChild(ul);
print_list(list[i].children, ul);
}
$("#jqxTree").appendChild(li);
}
}
sim("<%= list %>");
</script>
<ul id='jqxTree'>
</ul>
它在此行if (list[i].children.length > 0) {中给出了错误
无法读取未定义的属性“长度”
答案 0 :(得分：0)
您必须先解析JSON。如果将json作为String发送，请查看以下代码。
json = JSON.parse(list);
$.each(json, function(idx, obj) {
alert(obj.name + " - " + obj.children.length);
});