获取对象内部数组的长度

Question

i have the following object in javascript:

objectX which is an

Object {names : Array[14]}

im trying to get the length of this, but it returns undefined when i use objectX.length?

Im trying it in chrome debugger, and googling, anyone out there quickly let me know plz.

Answer 1

object.names.length

要么

object['names'].length

Answer 2

From the output it seems that the property name is 'name ' . See the differences in the console output:

> console.log({names: []});
Object {names: Array[0]}

> console.log({'names ': []});
Object {names : Array[0]}      // <- this looks like what you have
//           ^ note the space

So you'd have to do:

obj['names '].length

I suggest to fix the property name though, so that you can use obj.name.length instead.

Answer 3

Fix your object notation:

var obj = {name:Array(14)};
alert(obj.name.length);

var obj = {name : [1, 2, 3, 4]};
alert(obj.name.length);

Fiddle