Session.DataLayer Property

Gets the data access layer used by the current session to access a data store.

Namespace: DevExpress.Xpo

Assembly: DevExpress.Xpo.v19.2.dll

Declaration

C#

[Browsable(false)]
public IDataLayer DataLayer { get; }

VB.NET

<Browsable(False)>
Public ReadOnly Property DataLayer As IDataLayer

Property Value

Type	Description
IDataLayer	An object which implements the IDataLayer interface.

Example

This example demonstrates how to create a data layer that will be used by all Session objects.

The XpoDefault.DataLayer property’s value is null by default. XPO creates a new data layer for each session when the session is connected to a data store.

In this example, a data layer (represented by the SimpleDataLayer class object) is created and assigned to the XpoDefault.DataLayer property using the XpoDefault.GetDataLayer method.

In this case, newly created sessions will use this data layer. The sessions’ Session.Connection and Session.ConnectionString properties are not initialized.

C#

using DevExpress.Data.DB;
using DevExpress.Xpo;

string forcedConnectionString = ...;
XpoDefault.DataLayer = XpoDefault.GetDataLayer(forcedConnectionString, 
    AutoCreateOption.DatabaseAndSchema);

VB.NET

Imports DevExpress.Data.DB
Imports DevExpress.Xpo

Dim forcedConnectionString As String = ...
XpoDefault.DataLayer = XpoDefault.GetDataLayer(forcedConnectionString, _
    AutoCreateOption.DatabaseAndSchema)

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the DataLayer property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

XAF_how-to-generate-a-sequential-and-user-friendly-identifier-field-within-an-xpo-business-e4904/CS/Solution2.Module/BusinessObjects/TestUserFriendlyCodeObject.cs#L17

if(!(Session is NestedUnitOfWork)
    && (Session.DataLayer != null)
        && Session.IsNewObject(this)

XPO_how-to-generate-persistent-metadata-for-an-arbitrary-data-table-e2922/CS/MapArbitraryDatabaseExample/Form1.cs#L19

void BindProducts() {
    SimpleDataLayer dataLayer = (SimpleDataLayer)session1.DataLayer;
    ConnectionProviderSql provider = (ConnectionProviderSql)dataLayer.ConnectionProvider;

VB.NET

XAF_how-to-generate-a-sequential-and-user-friendly-identifier-field-within-an-xpo-business-e4904/VB/Solution2.Module/BusinessObjects/TestUserFriendlyCodeObject.vb#L24

Protected Overrides Sub OnSaving()
    If Not(TypeOf Session Is NestedUnitOfWork) AndAlso (Session.DataLayer IsNot Nothing) AndAlso Session.IsNewObject(Me) AndAlso (TypeOf Session.ObjectLayer Is SimpleObjectLayer) AndAlso String.IsNullOrEmpty(Code) Then
                'OR

XPO_how-to-generate-persistent-metadata-for-an-arbitrary-data-table-e2922/VB/MapArbitraryDatabaseExample/Form1.vb#L21

Private Sub BindProducts()
    Dim dataLayer As SimpleDataLayer = CType(session1.DataLayer, SimpleDataLayer)
    Dim provider As ConnectionProviderSql = CType(dataLayer.ConnectionProvider, ConnectionProviderSql)