Undefined behaviour in Json

Question

What should happen when the value of a property is set to undefined in a json string. i.e:

{"Name":undefined}

The following example is using the json.net library. An exception is thrown when de-serializing the object.

JsonConvert.DeserializeObject<SimpleObject>("{\"Name\":undefined}");

public class SimpleObject
{
  public string Name { get; set; }
}

Newtonsoft.Json.JsonReaderException was unhandled
  Message=Error reading string. Unexpected token: Undefined. Path 'Value', line 1, position 18.
  Source=Newtonsoft.Json
  LineNumber=1
  LinePosition=18
  Path=Value

score 1 · Accepted Answer · answered May 04 '12 at 20:30

I think the error is fine.

Jsonlint.org throws an error too.

And reading the documentation on json.org the "value" element may have the following variants:

string number object array true false null

As you can see, undefined is NOT listed. Object does also not count as undefined.

Undefined behaviour in Json

1 Answers1

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