How to XMLSerialize Collection Class

[hman]

Hi,

I have a collection class where I've implemeneted the
ICollection Interface.

Here is a small code segment.

public class PageList : ICollection, IComparer,
IEnumerable, IList
{
protected ArrayList _pages;

public PageList()
{
_pages = new ArrayList();
}
#region IList Members
public object this[int index]
{
get
{
if (index > _pages.Count)
{
return (Page)null;
}
else
{
return (Page)_pages
[index];
}
}
set
{
}
}

public int Add(object objPage)
{

int arrayIndexAdded = -1;
arrayIndexAdded = _pages.Add
(objPage);
return arrayIndexAdded ;
}

}

I have another class which declares this PageList class
and creates an instance of it.

How do I serialized this class?

[Christoph Schittko [MVP]]

Hman,

You should be able to serialize instances like this:

PageList pl = new PageList();

// populate pl

XmlSerializer ser = new XmlSerializer( typeof( PageList ), new Type[] {
... } ); // enumerate all the types in the list.
ser.Serialize( writer, pl );

be careful though ... if you don't know what the types in your List are,
then getting the Types from the list elements and instantiating a serializer
instance is a very expensive operation and if performance matters, then you
should probably alter your design to not go that route.

I also have a few questions about the PageList class. Why do you implement
everything by hand, is there any reason you don't derive from CollectionBase
or ? And why are you even implementing a custom List if you don't strongly
type it? You may just as well stick to the ArrayList.

--
HTH
Christoph Schittko [MVP, XmlInsider]
Software Architect, .NET Mentor
"hman" <an*******@disc ussions.microso ft.com> wrote in message
news:08******** *************** *****@phx.gbl.. .

Hi,

I have a collection class where I've implemeneted the
ICollection Interface.

Here is a small code segment.

public class PageList : ICollection, IComparer,
IEnumerable, IList
{
protected ArrayList _pages;

public PageList()
{
_pages = new ArrayList();
}
#region IList Members
public object this[int index]
{
get
{
if (index > _pages.Count)
{
return (Page)null;
}
else
{
return (Page)_pages
[index];
}
}
set
{
}
}

public int Add(object objPage)
{

int arrayIndexAdded = -1;
arrayIndexAdded = _pages.Add
(objPage);
return arrayIndexAdded ;
}

}

I have another class which declares this PageList class
and creates an instance of it.

How do I serialized this class?

Hi, thanks for your help.
Actually, I have another class (Survey) which has an
instance of my PageList class.

code segment:

public class Survey
{
//survey has a collection of pages
private PageList _pagesCol;
private Page _currentPage;

public Survey()
{
_pagesCol = new PageList();
Page defaultFirstPag e = new Page();
defaultFirstPag e.Name = "Page 1";
_pagesCol.Add (defaultFirstPa ge);
}

}

I am simply serializing an intance of Survey:

// Serialization
XmlSerializer s = new XmlSerializer(t ypeof(Survey));
TextWriter w = new StreamWriter(@" C:\SCSurvey.xml ");
s.Serialize(w, _survey);
w.Close();

where _survey is my Survey instance created elsewhere.
Why isn't my PageList intance serialized?
-
-I don't know what strongly types custom lists are.

-----Original Message-----
Hman,

You should be able to serialize instances like this:

PageList pl = new PageList();

// populate pl

XmlSerialize r ser = new XmlSerializer( typeof( PageList ), new Type[] { ... } ); // enumerate all the types in the list.
ser.Serializ e( writer, pl );

be careful though ... if you don't know what the types in your List are,then getting the Types from the list elements and instantiating a serializerinstance is a very expensive operation and if performance matters, then youshould probably alter your design to not go that route.

I also have a few questions about the PageList class. Why do you implementeverything by hand, is there any reason you don't derive from CollectionBaseor ? And why are you even implementing a custom List if you don't stronglytype it? You may just as well stick to the ArrayList.

--
HTH
Christoph Schittko [MVP, XmlInsider]
Software Architect, .NET Mentor
"hman" <an*******@disc ussions.microso ft.com> wrote in messagenews:08******* *************** ******@phx.gbl. ..

Hi,

I have a collection class where I've implemeneted the
ICollection Interface.

Here is a small code segment.

public class PageList : ICollection, IComparer,
IEnumerable, IList
{
protected ArrayList _pages;

public PageList()
{
_pages = new ArrayList();
}
#region IList Members
public object this[int index]
{
get
{
if (index > _pages.Count)
{
return (Page)null;
}
else
{
return (Page)_pages
[index];
}
}
set
{
}
}

public int Add(object objPage)
{

int arrayIndexAdded = -1;
arrayIndexAdded = _pages.Add
(objPage);
return arrayIndexAdded ;
}

}

I have another class which declares this PageList class
and creates an instance of it.

How do I serialized this class?

.

Got everything working. Thanks.

-----Original Message-----
Hi, thanks for your help.
Actually, I have another class (Survey) which has an
instance of my PageList class.

code segment:

public class Survey
{
//survey has a collection of pages
private PageList _pagesCol;
private Page _currentPage;

public Survey()
{
_pagesCol = new PageList();
Page defaultFirstPag e = new Page();
defaultFirstPag e.Name = "Page 1";
_pagesCol.Add (defaultFirstPa ge);
}

}

I am simply serializing an intance of Survey:

// Serialization
XmlSerialize r s = new XmlSerializer(t ypeof(Survey));
TextWriter w = new StreamWriter(@" C:\SCSurvey.xml ");
s.Serialize( w, _survey);
w.Close();

where _survey is my Survey instance created elsewhere.
Why isn't my PageList intance serialized?
-
-I don't know what strongly types custom lists are.

-----Original Message-----
Hman,

You should be able to serialize instances like this:

PageList pl = new PageList();

// populate pl

XmlSerializ er ser = new XmlSerializer( typeof(PageList ), new Type[] {

... } ); // enumerate all the types in the list.
ser.Serialize ( writer, pl );

be careful though ... if you don't know what the types

inyour List are,

then getting the Types from the list elements andinstantiatin g a serializer

instance is a very expensive operation and if

performancematters, then you

should probably alter your design to not go that route.

I also have a few questions about the PageList class.

Whydo you implement

everything by hand, is there any reason you don't derive

from CollectionBase

or ? And why are you even implementing a custom List if

you don't strongly

type it? You may just as well stick to the ArrayList.

--
HTH
Christoph Schittko [MVP, XmlInsider]
Software Architect, .NET Mentor
"hman" <an*******@disc ussions.microso ft.com> wrote in

message

news:08****** *************** *******@phx.gbl ...

Hi,

I have a collection class where I've implemeneted the
ICollection Interface.

Here is a small code segment.

public class PageList : ICollection, IComparer,
IEnumerable, IList
{
protected ArrayList _pages;

public PageList()
{
_pages = new ArrayList();
}
#region IList Members
public object this[int index]
{
get
{
if (index > _pages.Count)
{
return (Page)null;
}
else
{
return (Page)_pages
[index];
}
}
set
{
}
}

public int Add(object objPage)
{

int arrayIndexAdded = -1;
arrayIndexAdded = _pages.Add
(objPage);
return arrayIndexAdded ;
}

}

I have another class which declares this PageList class
and creates an instance of it.

How do I serialized this class?

.

.