Json Object Array Length

Question

I'm working with some Json that is similar to:

{ 
   "Apps" : [
   { 
     "Name" : "app1",
     "id" : "1",
     "groups" : [ 
       { "id" : "1", "name" : "test group 1", "desc" : "this is a test group" },
       { "id" : "2", "name" : "test group 2", "desc" : "this is another test group" } 
     ]
   }
   ]
}

If I parse it in jquery to return an object and I'm iterating through the apps like so:

$.each(myJsonObject.Apps, function() { ... };

How can I get the length of this.groups ?

I've tried

• this.groups.length
• this.groups.length()
• $(this).groups.length()

and I cannot find any decent documentation on multiple tier json objects that have good information.

Any links or examples or suggestions would be appreciated.

Answer 1

Try:

$.each(myJsonObject.Apps, function(i, obj) { ... });

obj.Groups.length;

Answer 2

Javascript is case sensitive. Change this.Groups.length to this.groups.length.

This code should work:

$.each(myJsonObject.Apps, function() { 
   alert(this.groups.length);
}); 

I have a working example on JSFiddle

To avoid this sort of problem, you should use a consistent capitalization. In Javascript, it is conventional to use camelCase.

Answer 3

this works well:

HTML:

<span id="result"></span>

JS:

var myJsonObject = 
{ 
   "Apps" : [
   { 
     "Name" : "app1",
     "id" : "1",
     "groups" : [ 
       { "id" : "1", "name" : "test group 1", "desc" : "this is a test group" },
       { "id" : "2", "name" : "test group 2", "desc" : "this is another test group" } 
     ]
   }
   ]
};

$.each(myJsonObject.Apps, function(i, el) { 
    $("#result").html(el.groups.length);
});

example