如何从 json 文件访问类别>平板电脑>desc？

Question

{
"categories":{
"tablet":{
"image":"1.png",
"desc" : "Tablet Description",
"button": "SHOP NOW!"   
},
"laptop":{
"image":"1.png",
"desc" : "Laptop Description",
"button": "SHOP NOW!" 
},
"monitor":{
"image":"1.png",
"desc" : "Monitor Description",
"button": "SHOP NOW!" 
}
}

我正在尝试使用以下代码，但无法获得它-

productList = JSON.parse("demo.json");
//console.log(productList.categories.tablet.desc);
for (category in productList.categories) {
console.log(category.desc);
}

但当我使用这条线时，外循环显示正确。

console.log(productList.categories.tablet.desc);

Answer 1

它不起作用，因为在for循环中，您得到了一个与类别中存在的直接子项相对应的键，并且您的desc属性是类别的grand-child，所以您要做的是：

categories.desc // desc property is not present in categoies.

尝试以下操作：

var productList = {"categories": {"tablet":{"image":"1.png","desc":"Tablet Description","button":"SHOP NOW!"},"laptop":{"image":"1.png","desc":"Laptop Description","button":"SHOP NOW!"},"monitor":{"image":"1.png","desc":"Monitor Description","button":"SHOP NOW!"}}};
for(category in productList.categories){
console.log(productList.categories[category].desc);
}

Answer 2

for (category in productList.categories) {
console.log(productList.categories[category].desc);
}

类别不会给你对象；它为您提供了访问productList.cacategories的密钥。