Javascript 访问不在数组中的json子对象

我试图访问一个不在数组中的json子对象。我试着用下面的脚本访问它，但它不起作用。我希望能够访问menuCategory对象

JSON

JAVASCRIPT

callEditMenu(parent, content) {
  this.modalService.open(content);
  this.editMenuCategoryId = parent.menuCategory.id;
}

可能是

const parent=[{“id”：67，“name”：“星期三菜单”，“serveDate”：“2019-06-12 00:00:00”，“expiryDate”：“2019-06-12 16:11:00”，“status”：“APPROVED”，“isEnabled”：true，“feeds”：[{“id”：45，“name”：“Waakye，Gari和Wele”，“description”：“为所有孩子设计的非常好的食物”，“图像”：“mealType”：“午餐”，“单价”：30，“status”：“ENABLED”}，{“id”：46，“name”：“Gari and Beans”，“description:“为所有孩子设计的非常好的食物”，“image:”“mealType:“午餐”，“单价”：12，“status:“ENABLED”}]，“menuCategory:{“id”：2，“name:“hello”}]
console.log（parent[0].menuCategory.id）；

如果callEditMenu函数中的parent参数引用的是您包含的JSON，请尝试

parent[0].menuCategory.id

let arr = [{"id":67,"name":"Wednesday Menu","serveDate":"2019-06-12 00:00:00","expiryDate":"2019-06-12 16:11:00","status":"APPROVED","isEnabled":true,"meals":[{"id":45,"name":"Waakye, Gari and Wele","description":"A very well designed food for all kids","image":"","mealType":"LUNCH","unitPrice":30,"status":"ENABLED"},{"id":46,"name":"Gari and Beans","description":"A very well designed food for all kidsss","image":"","mealType":"LUNCH","unitPrice":12,"status":"ENABLED"}],"menuCategory":{"id":2,"name":"hello"}}]

for (let item of arr)  {
  if (item.hasOwnProperty("menuCategory")) {
    console.log(item["menuCategory"]);
  }
};

let res = arr.filter((item) => item && item.menuCategory);
console.log(res[0].menuCategory);

---

如果您需要动态查找它。以上是两种不同的方法

考虑到对象数组中会有多个项，您可以遍历每个对象以获得菜单类别名称，如下所示

让obj=[
{
“id”：67，
“姓名”：“星期三菜单”，
“服务”：“2019-06-12 00:00:00”，
“到期日”：“2019-06-12 16:11:00”，
“状态”：“已批准”，
“isEnabled”：没错，
“膳食”：[
{
“id”：45，
“名称”：“Waakye、Gari和Wele”，
“描述”：“为所有孩子设计的非常好的食物”，
“图像”：“，
“mealType”：“午餐”，
“单价”：30，
“状态”：“已启用”
},
{
“id”：46，
“名称”：“Gari and Beans”，
“描述”：“为所有孩子设计的非常好的食物”，
“图像”：“，
“mealType”：“午餐”，
“单价”：12，
“状态”：“已启用”
}
],
“菜单分类”：{
“id”：2，
“姓名”：“你好”
}
}
];
对象forEach（elem=>{
log（elem.menuCategory.name）；
})；

let arr = [{"id":67,"name":"Wednesday Menu","serveDate":"2019-06-12 00:00:00","expiryDate":"2019-06-12 16:11:00","status":"APPROVED","isEnabled":true,"meals":[{"id":45,"name":"Waakye, Gari and Wele","description":"A very well designed food for all kids","image":"","mealType":"LUNCH","unitPrice":30,"status":"ENABLED"},{"id":46,"name":"Gari and Beans","description":"A very well designed food for all kidsss","image":"","mealType":"LUNCH","unitPrice":12,"status":"ENABLED"}],"menuCategory":{"id":2,"name":"hello"}}]

for (let item of arr)  {
  if (item.hasOwnProperty("menuCategory")) {
    console.log(item["menuCategory"]);
  }
};

let res = arr.filter((item) => item && item.menuCategory);
console.log(res[0].menuCategory);