Custom JavaScriptConverter for DateTime?

Question

I have an object, it has a DateTime property... I want to pass that object from an .ashx handler back to a webpage via AJAX/JSON... I don\'t want to use 3rd party controls..

Answer 1

Actually there is an ugly way, create a JavaScriptConverter for the container (Person/Article/Whatever) class

Container:

public class Article
{
    public int Id { get; set; }
    public string Title { get; set; }
    public DateTime Date { get; set; }
}

Converter:

public class ArticleJavaScriptConverter : JavaScriptConverter
{
    public override IEnumerable SupportedTypes
    {
        get { return new Type[] { typeof(Article) }; }
    }

    public override object Deserialize(
        IDictionary dictionary, 
        Type type, JavaScriptSerializer serializer)
    {
        DateTime date = 
            DateTime.ParseExact(dictionary["date"] as string, "s", null);

        return
            new Article()
            {
                Id = (int)dictionary["id"],
                Title = dictionary["title"] as string,
                Date = date
            };
    }

    public override IDictionary Serialize(
        object obj, JavaScriptSerializer serializer)
    {
        var article = obj as Article;
        var result = new Dictionary();

        if (article != null)
        {
            this.SerializeInternal(article, result);
        }

        return result;
    }

    private void SerializeInternal(
        Article article, IDictionary result)
    {
        result.Add("id", article.Id);
        result.Add("title", article.Title);
        result.Add("date", article.Date.ToString("s"));
    }
}

Happily ever after...

var serializer = new JavaScriptSerializer();

serializer.RegisterConverters(
    new JavaScriptConverter[] {
        new ArticleJavaScriptConverter() 
    });

var expected = new Article()
{
    Id = 3,
    Title = "test",
    Date = DateTime.Now
};


// {"id":3,"title":"test","date":"2009-12-02T05:12:00"}
var json = serializer.Serialize(article);

var actual = serializer.Deserialize
(json);

Assert.AreEqual(expected, actual);