javascript - 访问nodejs中各个级别的嵌套JSON对象

Question

我将数据存储在这样的变量中

var products = [
    {
        place1:[
            {id: 1, name: "choc1", price: 20},
            {id: 2, name: "choc2", price: 30}
        ],
        place2:[
            {id: 1, name: "coffee", price: 50}
        ],
        place3: [
            {id: 1, name: "oil1", price: 10},
            {id: 2, name: "oil2", price: 60},
            {id: 3, name: "oil3", price: 70}
        ]
    }
];

我想写一个get方法，让它响应这个Url

http://myurl.com/place1/1

获取方法的格式为

router.get('/:place/:id([0-9]{1,})', function(req, res){
//  send the exact data as requested
}

我不明白的是如何验证链接。即，验证该位置是否在 products 变量中，然后验证该 id 是否存在于该产品变量中，如果存在，则将其发送回服务器，否则发送错误响应。

Answer 1

这是使用点表示法从对象获取嵌套值的函数:

/**
 * Treating field name with dot in it as a path to nested value.
 * For example 'settings.day' is path to { settings: { day: 'value' } }
 *
 * @param {{}} object Object where to look for a key
 * @param {string} field Dot notated string, which is path to desired key
 * @returns {*}
 */
getNestedValue = function (object, field) {
    if (!object) {
        return null;
    }

    var path   = field.split('.');
    while (path.length && (object = object[path.shift()]));

    return object;
};