Question

This is an interview questions, Asked to write a Man class to let the following code can run properly:

var me =new  Man();

//method one:
me.attr("fullname", "tom");

//method two:
me.fullname = "jim";

console.info("my name is:" + me.attr("fullname"));

/*------[result is]------
my name is:tom
------------------*/

my answer is:

var Man=function(){
};

Man.prototype.attr=function(attr,val){
    if(val){
        this[attr]=val;
    }
    else{
        return this[attr];
    }
}

The results of my code to run is:

/*------[result is]------
my name is:jim
------------------*/

who can help me? thanks

Answer 1

You could make a second dictionary:

function Man() {
    this.dictionary = {};
}

Man.prototype.attr = function(attr, val) {
    if(arguments.length > 1) {
        this.dictionary[attr] = val;
    } else {
        return this.dictionary[attr];
    }
};

You could use a closed variable:

function Man() {
    var dictionary = {};

    this.attr = function(attr, val) {
        if(arguments.length > 1) {
            dictionary[attr] = val;
        } else {
            return dictionary[attr];
        }
    };
}

You could use a closed fullname variable, and ignore everything except 'fullname':

function Man() {
    var fullname;

    this.attr = function(attr, val) {
        if(attr === 'fullname') {
            if(arguments.length > 1) {
                fullname = val;
            } else {
                return fullname;
            }
        }
    };
}

You could also return "tom" every single time, or pretend all the attributes are "fullname", or both. You could ROT13 property names before assigning them. You could add underscores. You could create a property instead that throws away values beginning with "j". The possibilities are limitless, actually.