display JSON in a tree format

format_json.js

function render(data, indent, fromArray) {
    if(data == undefined){
        return '';
    }

    var preAppend = '';
    if(indent){
        preAppend = new Array(indent * 4 + 1).join(' ');
    }else{
        indent = 0;
    }

    var array = [];
    if(Array.isArray(data)){
        array.push('')
        data.forEach(function (item) {
            var value = render(item, indent, true);
            array.push(preAppend + value);
        });
    }else if(typeof data == 'object'){
        if(!fromArray && indent)
            array.push('');

        var first = true;
        for(var key in data){
            var value = data[key];
            var result = render(value, indent + 1);

            if(fromArray && first){
                array.push(key + ":" + result);
                first = false;
            }else{
                array.push(preAppend + key + ":" + result);    
            }
        }
    }else{
        return data;
    }

    return array.join('\n');
}


var info = {
    a: 1,
    b: 2,
    d: {
        a: 1,
        b: 2,
        c: {
            a: 1
        },
        e: [1,2,3]
    },
    e: [
        1,2,3
    ],
    f: [
        {
            a: 1,
            b: 2,
            d: [12,3,4,],
            e: {
                a: 1,
                b: 2
            },
            f: [
                {
                    a: 1
                }
            ]
        }
    ]
};
                var array = [];
                var xxx = render(info);
                console.log('\n\nend ====>>>>');
                console.log(xxx);
                // console.log(array.join('\n'));;

a:1
b:2
d:
    a:1
    b:2
    c:
        a:1
    e:
        1
        2
        3
e:
    1
    2
    3
f:
    a:1
    b:2
    d:
        12
        3
        4
    e:
        a:1
        b:2
    f:
        a:1