Of the data source controls that are included in the .NET Framework, only the ObjectDataSource control supports returning a single page of data.

public class PageRequestDataSource
{
    // выборка конкретной страницы
    //
    public DataTable SelectPage(int maximumRows, int startRowIndex)
    { ...    }

    // Общее количество записей в коллекции
    //
    public int RowCount()
    { ...    }
}

<asp:ObjectDataSource ID="RecordPageDataSource" runat="server" 
     EnablePaging="True" SelectMethod="SelectPage" TypeName="PageRequestDataSource"
     SelectCountMethod="RowCount">
</asp:ObjectDataSource>

To bind to a data source that implements the System.Collections.IEnumerable interface, programmatically set the DataSource property of the GridView control to the data source and then call the DataBind method. When using this method, the GridView control does not provide built-in sorting, updating, deleting, and paging functionality.

MC>Будм доказывать практическими лабами .

<asp:ObjectDataSource ID="MyDataSource" runat="server" Type="<%= typeof(My.MyDataManager) %>" ...>...

public class DataManager
{
    public List<Entity> GetAllEntities();
    public List<Entity> GetAllEntities(int maximumRows, int startRowIndex, string sortExpression);
    public int GetAllEntitiesCount();

    public List<Entity> GetEntitiesByName(string name);
    public List<Entity> GetEntitiesByName(string name, int maximumRows, int startRowIndex, string sortExpression);
    public int GetEntitiesByNameCount(string name);

    public Entity GetEntityById(int entityId);
    
    public void DeleteEntityById(int entityId);
    public void InsertEntity(Entity entity);
    public void UpdateEntity(Entity entity);
}

// Ну это понятно
//
ISelect
{
    IEnumerable Select();
}

// постраничная выборка
//
IPagable
{
    IEnumerable SelectPage(int PageNum, int PageSize, out int TotalCount);
}

// Кеширование
//
ICachable
{
    void Add<T>(string Key, T CacheObject)
    T Get<T>(string Key)
    void ClearCache();
  ICacheStrategy CacheStrategy { get; set; }    
}
    
// Сортировка
//
ISortable
{
    void Sort(string SortExpression)
}

//Обновление
//
IUpdatable
{
        void Update<T>(T BizObject);
}

public class BindAdapter : IPagable, ICachable, ISortable, IUpdatable
{
    ...
    
    private string _sortExpression  = "";
    void Sort(string SortExpression)
    {
        _sortExpression = SortExpression;
    }
    
    IEnumerable SelectPage(...)
    {
        TotalCount = DataManager.GetAllEntitiesCount();
        return DataManager.GetAllEntities(maximumRows, startRowIndex, _sortExpression);
    }
    
    ....
}

S>Давай, у нас грядет небольшой рефакторинг этой части, как раз будет кстати.

IB>// Ну это понятно
IB>//
IB>ISelect
IB>{
IB>    IEnumerable Select();
IB>}

IB>// постраничная выборка
IB>//
IB>IPagable
IB>{
IB>    IEnumerable SelectPage(int PageNum, int PageSize, out int TotalCount);
IB>}

IB>// Кеширование
IB>//
IB>ICachable
IB>{
IB>    void Add<T>(string Key, T CacheObject)
IB>    T Get<T>(string Key)
IB>    void ClearCache();
IB>  ICacheStrategy CacheStrategy { get; set; }    
IB>}
    
IB>// Сортировка
IB>//
IB>ISortable
IB>{
IB>    void Sort(string SortExpression)
IB>}

IB>//Обновление
IB>//
IB>IUpdatable
IB>{
IB>        void Update<T>(T BizObject);
IB>}
IB>

IB>public class BindAdapter : IPagable, ICachable, ISortable, IUpdatable
IB>{
IB>    ...
    
IB>    private string _sortExpression  = "";
IB>    void Sort(string SortExpression)
IB>    {
IB>        _sortExpression = SortExpression;
IB>    }
    
IB>    IEnumerable SelectPage(...)
IB>    {
IB>        TotalCount = DataManager.GetAllEntitiesCount();
IB>        return DataManager.GetAllEntities(maximumRows, startRowIndex, _sortExpression);
IB>    }
    
IB>    ....
IB>}
IB>

- ASPX ---------------------    - PresentationLogic --------------------------------    - Вне приложения -
GridView -> ObjectDataSource -> PresentationLogic.EntityPresenter -> WebServiceProxy -> WebService -> ...

- ASPX ---------------------    - PresentationLogic -----------------------------------------------------------------    - Вне приложения -
GridView -> ObjectDataSource -> PresentationLogic.EntityPresenter (тот самый условный DataManager) -> WebServiceProxy -> WebService -> ...

G>>>>З.Ы. ODS — это такой экспресс-враппер, сделанный для того чтобы быстро клепать небольшие приложения и не испугать новичков интерфейсами и прочей фигней

ObjectDataSource dataSource = new ObjectDataSource();
this.Controls.Add(dataSource);

dataSource.ID = "EmployeesDataSource";
dataSource.OldValuesParameterFormatString = "original_{0}";
dataSource.SelectMethod = "GetEmployes";
dataSource.TypeName = "EmployeesDataAdapter";
dataSource.EnablePaging = true;
dataSource.MaximumRowsParameterName = "pageSize";
dataSource.SelectCountMethod = "GetEmployeesCount";
dataSource.StartRowIndexParameterName = "startIndex";

Parameter sortParameter = new Parameter();
dataSource.SelectParameters.Add(sortParameter);

sortParameter.Name = "srotExpression";
sortParameter.Type = TypeCode.String;

this.GridView1.DataSourceID = dataSource.ID;

.....cs
public class Adapter
{
  IEnumerable  SelectMethod()
    {
        
    }
}

.....aspx
<asp:ObjectDataSource ... SelectMethod="SelectMethod" TypeName="Adapter">

.....cs
public class Adapter : ISelectable
{
  IEnumerable  ISelectable.SelectMethod()
    {
        
    }
}

// использовать можно в .cs - файле
//
GridView.SetSelectable = Adapter;

// Или, если очень хочется использовать .aspx, то можно по старинке
//
.....aspx
<asp:ObjectDataSource ... TypeName="Adapter">

throw new HttpException(SR.GetString("Ambiguous_type", new object[] { typeName, Util.GetAssemblySafePathFromType(type1), Util.GetAssemblySafePathFromType(type2) }));

S>>throw new HttpException(SR.GetString("Ambiguous_type", new object[] { typeName, Util.GetAssemblySafePathFromType(type1), Util.GetAssemblySafePathFromType(type2) }));
S>>

S>>

 BuildManager._theBuildManager.EnsureTopLevelFilesCompiled();
    type1 = Util.GetTypeFromAssemblies(BuildManager.TheBuildManager.TopLevelReferencedAssemblies, typeName, ignoreCase);
    if (type1 != null)
    {
                return type1;
    }

Type type1 = null;
if (Util.TypeNameContainsAssembly(typeName))
{
       type1 = Type.GetType(typeName, throwOnError, ignoreCase);
       if (type1 != null)
       {
            return type1;
       }
}

//Class1 cc = new Class1();
//cc.Aa = "asd";

Assembly[] assemblies = AppDomain.CurrentDomain.GetAssemblies();
foreach (Assembly assembly in assemblies)
{
    Type t = assembly.GetType("TryDataSourceProject.Class1");

    if (t != null)
    {
        this.Response.Write(t);
        this.Response.Write("\r\n");
        this.Response.Write(assembly);
    }
}

MC>Type type1 = null;
MC>if (Util.TypeNameContainsAssembly(typeName))
MC>{
MC>       type1 = Type.GetType(typeName, throwOnError, ignoreCase);
MC>       if (type1 != null)
MC>       {
MC>            return type1;
MC>       }
MC>}
MC>

Microsoft.Web.Services3.Configuration.WebServicesConfiguration, Microsoft.Web.Services3, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35

MC>//Class1 cc = new Class1();
MC>//cc.Aa = "asd";

MC>Assembly[] assemblies = AppDomain.CurrentDomain.GetAssemblies();
MC>foreach (Assembly assembly in assemblies)
MC>{
MC>    Type t = assembly.GetType("TryDataSourceProject.Class1");

MC>    if (t != null)
MC>    {
MC>        this.Response.Write(t);
MC>        this.Response.Write("\r\n");
MC>        this.Response.Write(assembly);
MC>    }
MC>}
MC>

Assembly[] assemblies = AppDomain.CurrentDomain.GetAssemblies();
foreach (Assembly assembly in assemblies)
{
    Type t = assembly.GetType("TryDataSourceProject.Class1");

    if (t != null)
    {
        this.Response.Write(t);
        this.Response.Write("\r\n");
        this.Response.Write(assembly);
    }
}

Class1 cc = new Class1();
cc.Aa = "asd";

Assembly[] assemblies = AppDomain.CurrentDomain.GetAssemblies();
foreach (Assembly assembly in assemblies)
{
    Type t = assembly.GetType("TryDataSourceProject.Class1");

    if (t != null)
    {
        this.Response.Write(t);
        this.Response.Write("\r\n");
        this.Response.Write(assembly);
    }
}