String.prototype.parseJSON = function () {
    try {
        return !(/[^,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]/.test(
                this.replace(/"(\\.|[^"\\])*"/g, ''))) &&
            eval('(' + this + ')');
    } catch (e) {
        return false;
    }
};