SimpleJSON: JSON encode, decode without default parser (pure javascript JSON parser)

simplejson.js

// SimpleJSON: JSON encode, decode without default (pure javascript JSON parser)
// Go Namhyeon <gnh1201@gmail.com>
// https://github.com/gnh1201
// MIT license

var $ = {};

/**
 * Decode JSON
 *
 * @param string jsonString - JSON text
 *
 * @return object
 */
$.json.decode = function(jsonString) {
    return (new Function("return " + jsonString)());
};

/**
 * Encode JSON
 *
 * @param object obj - Key/Value object
 *
 * @return string
 */
$.json.encode = function(obj) {
    var items = [];
    var isArray = (function(_obj) {
        try {
            return (_obj instanceof Array);
        } catch (e) {
            return false;
        }
    })(obj);
    var _toString = function(_obj) {
        try {
            if(typeof(_obj) == "object") {
                return $.json.encode(_obj);
            } else {
                var s = String(_obj).replace(/"/g, '\\"');
                if(typeof(_obj) == "number" || typeof(_obj) == "boolean") {
                    return s;
                } else {
                    return '"' + s + '"';
                }
            }
        } catch (e) {
            return "null";
        }
    };

    for(var k in obj) {
        var v = obj[k];

        if(!isArray) {
            items.push('"' + k + '":' + _toString(v));
        } else {
            items.push(_toString(v));
        }
    }

    if(!isArray) {
        return "{" + items.join(",") + "}";
    } else {
        return "[" + items.join(",") + "]";
    }
};

/**
 * Test JSON
 *
 * @param object obj - Key/Value object
 *
 * @return boolean
 */
$.json.test = function(obj) {
    var t1 = obj;
    var t2 = $.json.encode(obj);
    $.echo($.json.encode(t1));

    var t3 = $.json.decode(t2);
    var t4 = $.json.encode(t3);
    $.echo(t4);

    if(t2 == t4) {
        $.echo("success");
        return true;
    } else {
        $.echo("failed");
        return false;
    }
};

/**
 * Echo
 *
 * @param string txt
 *
 * @return void
 */
$.echo = function(txt) {
    if($.isWScript()) {
        WScript.Echo(txt);
    } else {
        try {
            window.alert(txt);
        } catch (e) {
            console.log(txt);
        }
    }
};

/**
 * Check if WScript
 *
 * @return bool
 */
$.isWScript = function() {
    return typeof(WScript) !== "undefined";
}

// test your data
var t1 = {"a": 1, "b": "banana", "c": {"d": 2, "e": 3}, "f": [100, 200, "3 hundreds", {"g": 4}]};
$.json.test(t1);

See also: https://github.com/gnh1201/welsonjs