获取对象属性的长度，该对象属性是对象数组的属性

Question

So, I want to get the length of an object property which is a property of an array of objects.

I want to get the length of actionDetails .

I tried the following: message[0].actionDetails[0].length; but this is resulting in undefined.

The data goes like this:

message=   [  
       {  
          "data":"1",
          "actionDetails":[  
             {  
                "type":"action",
                "url":"http:\/\/localhost\/app\/dashboard"
             },
             {  
                "type":"action",
                "url":"http:\/\/localhost\/app\/dashboard"
             },
             {  
                "type":"action",
                "url":"http:\/\/localhost\/app\/dashboard"
             }
    ]

Answer 1

I tried the following: message[0].actionDetails[0].length; but this is resulting in undefined.

Almost there, you don't need to get 0 th index of the array first whose length you are looking for

message[0].actionDetails.length;