Data Sets and Tables
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The raw DataSet and DataTable types are serializable, marked with the Serializable attribute:
[Serializable]
public class DataSet : ...
{...}
[Serializable]
public class DataTable : ...
{...}
We can define valid service contracts that accept or return data tables or data sets:
[DataContract]
struct Contact
{...}
[ServiceContract]
interface IContactManager
{
[OperationContract]
void AddContact(Contact contact);
[OperationContract]
void AddContacts(DataTable contacts);
[OperationContract]
DataTable GetContacts( );
}
Example:
[Serializable]
public partial class MyDataSet : DataSet
{
public ContactsDataTable Contacts
{get;}
[Serializable]
public partial class ContactsDataTable : DataTable,IEnumerable
{
public void AddContactsRow(ContactsRow row);
public ContactsRow AddContactsRow(string FirstName,string LastName);
//More members
}
public partial class ContactsRow : DataRow
{
public string FName
{get;set;}
public string LName
{get;set;}
//More members
}
//More members
}
public partial class ContactsTableAdapter : Component
{
public file MyDataSet.ContactsDataTable GetData( );
//More members
}
DataTableHelper
It requires is a converter from a data row in the table to the data contract. DataTableHelper also adds some compile-time and runtime type-safety verification
Exapmle: Using DataTableHelper
[DataContract]
struct Contact
{
[DataMember]
public string FName;
[DataMember]
public string LNamee;
}
[ServiceContract]
interface IContactManager
{
[OperationContract]
Contact[] GetContacts( );
...
}
class ContactManager : IContactManager
{
public Contact[] GetContacts( )
{
ContactsTableAdapter adapter = new ContactsTableAdapter( );
MyDataSet.ContactsDataTable contactsTable = adapter.GetData( );
Converter<MyDataSet.ContactsRow,Contact> converter;
Converter = delegate(MyDataSet.ContactsRow row)
{
Contact contact = new Contact( );
contact.FName = row.FName;
contact.LNamee = row.LNamee;
return contact;
};
return DataTableHelper.ToArray(contactsTable,converter);
}
//Rest of the implementation
}
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