Javascript 获取对象中数组的大小
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时间：2020-08-23 19:13:42 来源:igfitidea点击:
Getting the size of an array in an object
提问by meli
I would like some help with getting the size of an array inside an object:
我想要一些关于获取对象内数组大小的帮助：
var st = { "itema":{...},"itemb":[{"id":"s01","cd":"c01","dd":"d01",....}{"id":"s02","cd":"c02","dd":"d02",....}]}
How would you get a count of the objects inside "itemb"(in this case 2)?
您将如何获得内部对象的数量"itemb"（在本例中为 2）？
回答by Andrew Hare
Javascript arrays have a length property. Use it like this:
Javascript 数组有一个 length 属性。像这样使用它：
st.itemb.length
回答by BrunoLM
Arrays have a property .lengththat returns the number of elements.
数组具有.length返回元素数量的属性。
var st =
{
"itema":{},
"itemb":
[
{"id":"s01","cd":"c01","dd":"d01"},
{"id":"s02","cd":"c02","dd":"d02"}
]
};
st.itemb.length // 2
