Question

I have a json object like this:

[{
    "thing": "Top",
    "data": {
        "childs": [{
            "thing": "a",
            "data": {
                "text": "sdfgdg1",
                "morestuff": {
                    "thing": "Top",
                    "data": {
                        "childs": [{
                            "thing": "a",
                            "data": {
                                "text": "sdfg2",
                                "morestuff": "",
                            }
                        },
                        {
                            "thing": "a",
                            "data": {
                                "text": "gfhjfghj3",
                                "morestuff": {
                                    "thing": "Top",
                                    "data": {
                                        "childs": [{
                                            "thing": "a",
                                            "data": {
                                                "text": "asdfsadf 2 4",
                                                "morestuff": {
                                                    "thing": "Top",
                                                    "data": {
                                                        "childs": [{
                                                            "thing": "a",
                                                            "data": {
                                                                "text": "asdfsadf 2 5",
                                                                "morestuff": {
                                                                    "thing": "Top",
                                                                    "data": {
                                                                        "childs": {
                                                                            "thing": "a",
                                                                            "data": {
                                                                                "text": "asdfsadf 2 6",
                                                                                "morestuff": "",
                                                                            },
                                                                            "data": {
                                                                                "text": "asdfsadf 2 6",
                                                                                "morestuff": "",
                                                                            }
                                                                        },
                                                                    }
                                                                },
                                                            }
                                                        }],
                                                    }
                                                },
                                            }
                                        }],
                                    }
                                },
                            }
                        }],
                    }
                },
            }
        },
        {
            "thing": "a",
            "data": {
                "text": "asdfasd1 2",
                "morestuff": {
                    "thing": "Top",
                    "data": {
                        "childs": [{
                            "thing": "a",
                            "data": {
                                "text": "asdfsadf 2 3",
                                "morestuff": "",
                            }
                        }],
                    }
                },
            }
        },
        {
            "thing": "a",
            "data": {
                "text": "dfghfdgh 4",
                "morestuff": "",
            }
        }],
    }
}]  

…and I’m trying to iterate through it and get a total count on the “text” objects.

I can’t seem to be able to get something recursive working.. I think I’m missing a base-level understanding of both json and recursion..

After a couple of days of variations on this:

count=0;
c2=0;
c3=0;
function ra(arr){
    //console.log(arr.data.morestuff)
    if(arr!==undefined && arr.data && arr.data.morestuff===""){
        c3++;

    }else if((arr && arr.data && typeof arr.data.morestuff==="object")){
            if(arr.data.morestuff.data.childs.length>1){
                for(var w=0;w<arr.data.morestuff.data.childs.length;w++){
                    count+=ra(arr.data.morestuff.data.childs[w])
                }
            }else{
                count+=ra(arr.data.morestuff.data.childs[0])
            }
    }
         return(c3)
}
countn=0;//top morestuff with no morestuff
tot=0;
function reps(obj){
tot=obj.data.childs.length;
console.log("tot="+tot)
    for(var x=0;x<tot;x++){
        tot+=ra(obj.data.childs[x])
        c3=0
        if(tot>1000){//trying to prevent a runaway loop somehwere
            break;
        }
    }
    console.log(tot)
}

reps(json[0]); 

I’ve come to the conclusion that I just don’t know. I get all kinds of different results; some have come close by adding together the returns from the ra method, but nothing consistant (i.e. wrong) and always off by at least a few.

The JSON is consistent, though there are un-known numbers of children and childrens children which is why I’m looking to recursion.

Here is a fiddle: http://jsfiddle.net/CULVx/

Ideally, I’d like to count each text object, its’ relative position, and the number of children it has, but I figure I can mess with getting that stuff into an array if I could just get the counting working…

NB: I’ve tried jsonParse and other libraries to no avail. In particular, jsonParse throws an Object has no method "match" error when trying to use it on this json.

Answer 1

If you just want all "text" properties at any depth, then this should be sufficient: http://jsfiddle.net/QbpqT/.

You have a property key twice, though ("data" in the most nested object). Since an object cannot contain two properties with the same key, so you actually have 9 "text" properties; not 10.

var count = 0;

function iterate(obj) {
    for(var key in obj) { // iterate, `key` is the property key
        var elem = obj[key]; // `obj[key]` is the value

        if(key === "text") { // found "text" property
            count++;
        }

        if(typeof elem === "object") { // is an object (plain object or array),
                                       // so contains children
            iterate(elem); // call recursively
        }
    }
}

iterate(data); // start iterating the topmost element (`data`)

console.log(count); // 9