Problem when serializing class that implements IEnumerable

[Craig Buchanan]

I have a class called LineItems. It implements IEnumerable. It uses an
ArrayList to hold objects. When I try to serialize the object that contains
LineItems (an object called Order), I get an error that reads:

You must implement the Add(System.Object) method on LineItems because it
inherits from IEnumerable.

I've implemented GetEnumerator on the LineItems class. I also have two Add
methods.

What am I missing?

Thanks,

Craig Buchanan

 

[Vladimir Sadov [MSFT]]

Hi Craig,

I tried to follow your description and everything worked as expected. Can
you provide more deatails on what you are doing?

Thanks,
Vladimir [VB.Net team]


--------------------
| From: "Craig Buchanan" <[email protected]>
| Subject: Problem when serializing class that implements IEnumerable
| Date: Thu, 29 Jan 2004 09:51:35 -0600
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| X-Tomcat-NG: microsoft.public.dotnet.languages.vb
|
| I have a class called LineItems. It implements IEnumerable. It uses an
| ArrayList to hold objects. When I try to serialize the object that
contains
| LineItems (an object called Order), I get an error that reads:
|
| You must implement the Add(System.Object) method on LineItems because it
| inherits from IEnumerable.
|
| I've implemented GetEnumerator on the LineItems class. I also have two
Add
| methods.
|
| What am I missing?
|
| Thanks,
|
| Craig Buchanan
|
|
|

 

[Guest]

I've got the exact same problem

A strongly typed collection that implements IEnumerable. and is marked as serializable

Attempting to use the following on a consumer of the clas

Dim swWriter As New System.IO.StringWrite
Dim xsSerializer As New System.Xml.Serialization.XmlSerializer(GetType(DiscussionAreas)

gives the message
"You must implement the Add(System.Object) method on StrongTypes.DiscussionAreas because it inherits from IEnumerable.

The header of the class is as follow

Imports System.Xml.Serializatio

<XmlInclude(GetType(DiscussionAreas)), Serializable()>
Public Class DiscussionArea
Implements IEnumerabl

Certainly not inheriting...

Any ideas?

 

[Charles Law]

Hi Craig

What does you implementation of Add look like for the class DiscussionAreas?

Charles

I've got the exact same problem.

A strongly typed collection that implements IEnumerable. and is marked as serializable.

Attempting to use the following on a consumer of the class

Dim swWriter As New System.IO.StringWriter
Dim xsSerializer As New System.Xml.Serialization.XmlSerializer(GetType(DiscussionAreas))

gives the message
"You must implement the Add(System.Object) method on

StrongTypes.DiscussionAreas because it inherits from IEnumerable."

 

[Guest]

nothing special but it doesn't contain the system.object method..

Public Sub Add(ByVal DiscussionArea As DiscussionArea

It's confusing why it mentions inheritance. when clearly I'm implementing

 

[Charles Law]

Hi Craig

I suspect that if you implement it as

Public Sub Add(ByVal DiscussionArea As Object)

then the problem will go away. It suggests that when the serializer
reads/writes the file it sees the item as type Object and doesn't recognise
its real type.

Another minor point: I try to avoid naming variables and parameters with the
same name as classes. It avoids any confusion for the compiler and reader.

HTH

Charles