Javascript中，Array.isArray()判断问题

Question

有以下数据：

[{"children":[{"id":886,"name":"new subcategory1"},{"id":887,"name":"new subcategory2"}],"id":885,"name":"new main category1","shopId":125},{"children":[{"id":889,"name":"new subcategory3"},{"id":890,"name":"new subcategory4"}],"id":888,"name":"new main category2","shopId":125},{"children":[{"id":892,"name":"new subcategory5"},{"id":893,"name":"new subcategory6"}],"id":891,"name":"new main category3","shopId":125},{"children":[{"id":895,"name":"new subcategory7"},{"id":896,"name":"new subcategory8"}],"id":894,"name":"new main category4","shopId":125},{"children":[{"id":898,"name":"new subcategory9"},{"id":899,"name":"new subcategory10"}],"id":897,"name":"new main category5","shopId":125}]

然后我使用Arrays.isArray()判断，结果是false，应该返回true才对啊

Answer 1

你的结果是字符串把，用typeof 看看类型

Answer 2

Answer 3

Array.isArray([{"children":[{"id":886,"name":"new subcategory1"},{"id":887,"name":"new subcategory2"}],"id":885,"name":"new main category1","shopId":125},{"children":[{"id":889,"name":"new subcategory3"},{"id":890,"name":"new subcategory4"}],"id":888,"name":"new main category2","shopId":125},{"children":[{"id":892,"name":"new subcategory5"},{"id":893,"name":"new subcategory6"}],"id":891,"name":"new main category3","shopId":125},{"children":[{"id":895,"name":"new subcategory7"},{"id":896,"name":"new subcategory8"}],"id":894,"name":"new main category4","shopId":125},{"children":[{"id":898,"name":"new subcategory9"},{"id":899,"name":"new subcategory10"}],"id":897,"name":"new main category5","shopId":125}])

是 true 啊

Answer 4

Array.isArray(2) //false
Array.isArray([]) //true

//判断一个对象是否为数组

function isArray(obj) {
    return Object.prototype.toString.call(obj) == "[object Array]";
}
isArray([])    //true