计算本地存储中的键数

Question

对于简单的本地存储，我们使用 localstorage.length。但我使用的插件 localStorageDB 具有 JSON 输出，如下所示。我想数 "cart" 个项目（'data' -> 'cart'）。

此外，每当我添加产品时，localstorage.length 都会给出 1 的输出。然而，产品添加在 'data'->'cart'.

中

{
"tables": {
    "cart": {
        "fields": [
            "ID",
            "item",
            "quantity",
            "cost"
        ],
        "auto_increment": 3
    }
},
"data": {
    "cart": {
        "1": {
            "ID": 1,
            "item": "Nature Fresh Atta Chakki Fresh 10 kg",
            "quantity": "1",
            "cost": "252"
        },
        "2": {
            "ID": 2,
            "item": "Fortune Refined Oil Soya Bean 1 Lt",
            "quantity": "1",
            "cost": "85"
        }
    }
}}

更多信息：我使用“cart.serialize()”插件语法获得了序列化输出 Screenshot

Answer 1

syntax: Object.keys(obj).length);


var data = {
        "tables": {
            "cart": {
                "fields": [
                    "ID",
                    "item",
                    "quantity",
                    "cost"
                ],
                "auto_increment": 3
            }
        },
        "data": {
            "cart": {
                "1": {
                    "ID": 1,
                    "item": "Nature Fresh Atta Chakki Fresh 10 kg",
                    "quantity": "1",
                    "cost": "252"
                },
                "2": {
                    "ID": 2,
                    "item": "Fortune Refined Oil Soya Bean 1 Lt",
                    "quantity": "1",
                    "cost": "85"
                }
            }
        }
    }

console.log(Object.keys(data['data']['cart']).length);

Answer 2

localStorageDB 插件具有内置方法 rowCount() 用于计算 table.

中的条目

所以，像这样的东西应该可以工作：yourLib.rowCount('cart')

计算本地存储中的键数

Count number of keys in localstorage

html

javascript

json

local-storage