XML serialization of an Hashtable

[francois]

Hi,

I have a webservice that I am using and I would like it to return an XML
serialized version of an object.

the class of the object is defined serializable as the following:

[Serializable]
public class Event
{
}

Also it contains 5 properties returning simple data type such as int and
string. But one of them is an Hashtable. When I run my project i got a run
time exception telling me that :

System.InvalidOperationException: There was an error reflecting type
'Bos.BizObj.Event'. ---> System.NotSupportedException: The type
System.Collections.Hashtable is not supported because it implements
IDictionary.
at System.Xml.Serialization.TypeScope.GetCollectionElementType(Type type)

Then my question is:
How can I make the Hashtable serializable to make in turn my Event class
serializable?

Also I am a little bit surprised as in the .Net framework reference it is
specified that the
Hashtable class implement the serializable interface... Then it is puzzling
me even more

Thanks a lot,

Francois

 

[Tamir Khason]

using System;

using System.Collections;

using System.Runtime.Serialization.Formatters.Binary;

using System.IO;


namespace ConsoleApplication5

{

[Serializable]

struct name

{

public string forname;

public string familyname;

}



[Serializable]

struct address

{

public string street;

public int number;

}



class clsDataBlock

{



public static Hashtable NameToAddress = new Hashtable ();



[STAThread]

static void Main(string[] args)

{

clsDataBlock db=new clsDataBlock ();

string ans="";



while("x" != ans)

{

System.Console.WriteLine ("1 to enter new");

System.Console.WriteLine ("2 to search");

System.Console.WriteLine ("3 to save (serialize)");

System.Console.WriteLine ("4 to load (deserialize)");

System.Console.WriteLine ("5 to show data");

System.Console.WriteLine ("x to quit");

System.Console.WriteLine ("-----------------------");



ans = System.Console.ReadLine ();



switch(ans)

{

case "1":db.AddNew();

break;

case "2":db.Search();

break;

case "3":db.Save();

break;

case "4":db.Load();

break;

case "5":db.Show();

break;

}

}

}

public void AddNew()

{

name nm;

address ad;

string ans;

System.Console.WriteLine ("enter first name (x to exit):");

ans = System.Console.ReadLine();

nm.forname = ans;



System.Console.WriteLine ("enter last name (x to exit):");

ans = System.Console.ReadLine();

nm.familyname = ans;



System.Console.WriteLine ("enter street name (x to exit):");

ans = System.Console.ReadLine();

ad.street = ans;



System.Console.WriteLine ("enter street number (x to exit):");

ans = System.Console.ReadLine();

ad.number = int.Parse (ans);



NameToAddress.Add(nm,ad);

}



public void Search()

{

name nm2;



string ans2;

System.Console.WriteLine ("enter first name:");

ans2 = System.Console.ReadLine ();

nm2.forname = ans2;



System.Console.WriteLine ("enter last name:");

ans2 = System.Console.ReadLine ();

nm2.familyname = ans2;



System.Console.WriteLine ("working...");



object sname = NameToAddress[nm2];

if (sname != null)

{

address ad2 = (address)sname;

System.Console.WriteLine(" address: "+ ad2.street + " " +
ad2.number );

}

else

System.Console.WriteLine ("no name like that...");



}



public void Save()

{

FileStream fs = new FileStream ("Store.dat",FileMode.OpenOrCreate
,FileAccess.Write );

try

{

Hashtable a = new Hashtable();

a = NameToAddress;

BinaryFormatter bf=new BinaryFormatter ();

bf.Serialize (fs,a );

}

finally

{

fs.Close ();

}





}

public void Load()

{

FileStream fs = new FileStream ("Store.dat",FileMode.Open
,FileAccess.Read );

try

{

Hashtable a = new Hashtable();





BinaryFormatter bf=new BinaryFormatter ();

a=(Hashtable)bf.Deserialize (fs);

NameToAddress = a;

}

finally

{

fs.Close ();

}





}

public void Show()

{

name nm3;

address ad3;

foreach (DictionaryEntry entry in NameToAddress )

{

nm3 = (name)entry.Key;

ad3 = (address)entry.Value;

Console.WriteLine ("name= {0} {1}, address= {2} {3}",

nm3.forname,nm3.familyname ,ad3.street ,ad3.number);

}

}

}

}
Hope it helps
--
Tamir Khason
You want dot.NET? Just ask:
"Please, www.dotnet.us "

Hi,

I have a webservice that I am using and I would like it to return an XML
serialized version of an object.

the class of the object is defined serializable as the following:

[Serializable]
public class Event
{
}

Also it contains 5 properties returning simple data type such as int and
string. But one of them is an Hashtable. When I run my project i got a run
time exception telling me that :

System.InvalidOperationException: There was an error reflecting type
'Bos.BizObj.Event'. ---> System.NotSupportedException: The type
System.Collections.Hashtable is not supported because it implements
IDictionary.
at System.Xml.Serialization.TypeScope.GetCollectionElementType(Type type)

Then my question is:
How can I make the Hashtable serializable to make in turn my Event class
serializable?

Also I am a little bit surprised as in the .Net framework reference it is
specified that the
Hashtable class implement the serializable interface... Then it is puzzling
me even more

Thanks a lot,

Francois