How to check if an object is null

Question

Here is my code:

public static class SerializationUtil
{
    public static string Serialize(object obj)
    {
        if (obj == null)
            return string.Empty;

        StringWriter writer = new StringWriter();
        new System.Web.UI.LosFormatter().Serialize(writer, obj);
        return writer.ToString();
    }

    public static object Deserialize(string data)
    {
        if (data == null)
            return null;
        return (new System.Web.UI.LosFormatter()).Deserialize(data);
    }
}

The problem I am having is: When I call the serialize method if the obj is null it throws an error. So i would like to check if the obj value is null or not. The code I have i place now does not work as when the obj value is checked its never null.

Resolved:

See my post in answers

Exactly where is the exception thrown? Do you have the stack trace from the exception? — Fredrik Mörk
– Fredrik Mörk, Commented Aug 21, 2010 at 5:36
it is thrown at new System.Web.UI.LosFormatter().Serialize(writer, obj); — Luke101
– Luke101, Commented Aug 21, 2010 at 5:38
Can you also put in the exception details including the stack trace in the post as Fredrik suggested? — Jagmag
– Jagmag, Commented Aug 21, 2010 at 5:41
Unrelated to your question, but since Serialize generates an empty string instead of null, perhaps Deserialize should accept an empty string in addition to null. — Timwi
– Timwi, Commented Aug 21, 2010 at 6:32

Luke101 · Accepted Answer · 2010-08-21 05:46:20Z

2

OK, I have figured it out. I looked at the details of the exception and it expected the object class to be serializable. I made the class serializable and it worked

using System;

[Serializable]  //the missing piece
public class RegisterFormData
{
    public string username { get; set; }
    public string pass1 { get; set; }
    public string pass2 { get; set; }
    public string email { get; set; }
    public string firstname { get; set; }
    public string lastname { get; set; }
}

answered Aug 21, 2010 at 5:46

Luke101

65.7k89 gold badges247 silver badges377 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Mitch Wheat Over a year ago

you know, I was going to suggest that in the comments, and then thougth it couldn't possibly be because of that, could it?

Dan Tao · Accepted Answer · 2010-08-21 05:44:05Z

1

I really don't think that what you're describing is possible. If you've checked that obj is not null only a few lines above, then it is not null. If you're getting a NullReferenceException it is likely due to something else being null, possibly within the Serialize method itself.

answered Aug 21, 2010 at 5:44

Dan Tao

129k57 gold badges309 silver badges451 bronze badges

Collectives™ on Stack Overflow

How to check if an object is null

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related