Question

如何获取此JSON中的元素数量？

gettingTheLocalStorageData = {
  "sortable2": {
    "content": "example_panel_2",
    "columns": "3",
    "panel-size": "large",
    "childs": {
      "item-1-sortable2": {
        "header": "Feeds 1 ",
        "body": ""
      },
      "item-2-sortable2": {
        "header": "Feeds 2",
        "body": ""
      },
      "item-3-sortable2": {
        "header": "Feeds 3",
        "body": ""
      },
      "item-4-sortable2": {
        "header": "Feeds 4",
        "body": ""
      },
      "item-5-sortable2": {
        "header": "Feeds 5",
        "body": ""
      }
    }
  },
  "sortable3": {
    "content": "example_panel_3",
    "columns": "3",
    "panel-size": "large",
    "childs": {
      "item-0-sortable3": {
        "header": "Feeds 1 ",
        "body": ""
      },
      "item-1-sortable3": {
        "header": "Feeds 2",
        "body": ""
      },
      "item-2-sortable3": {
        "header": "Feeds 3",
        "body": ""
      },
      "item-3-sortable3": {
        "header": "Feeds 4",
        "body": ""
      },
      "item-4-sortable3": {
        "header": "Feeds 5",
        "body": ""
      }
    }
  }
}

这应该返回2个项目（sortable2，sortable3），但它返回的是659。我尝试过的几个步骤是：

console.log(gettingTheLocalStorageData .length); // = 659

和

console.log(Object.keys(gettingTheLocalStorageData).length); // = 659

任何可能的解决方案？

https://imgur.com/a/yGteda7我回来了什么

Answer 1

您可以使用Object.keys()：

Object.keys(getLocalStoragedata).length

Answer 2

我只需要解析它就可以了。

已添加

 gettingTheLocalStorageData = JSON.parse(gettingTheLocalStorageData);

现在它返回正确的数字

与@Deda一样

Answer 3

首先解析JSON

let parsed = JSON.parse(getLocalStoragedata)
console.log(Object.keys(parsed).length); // 2

获取JSON对象元素的数量

3 个答案: