ASPxTreeList.DataSource Property

Gets or sets the ASPxTreeList’s data source.

Namespace: DevExpress.Web.ASPxTreeList

Assembly: DevExpress.Web.ASPxTreeList.v20.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

public override object DataSource { get; set; }

VB.NET

Public Overrides Property DataSource As Object

Property Value

Type	Description
Object	An object which represents the data source from which the ASPxTreeList retrieves its data.

Example

This example shows how to bind the ASPxTreeList to data created at runtime.

Note

To correctly restore from the ViewState, a tree list needs data. When binding to data created at runtime, you must bind the tree list within the Page_Init event. Don’t handle the Page_Load event because it is fired after the ViewState has been restored.

C#

using System.Data.OleDb;
using DevExpress.Web.ASPxTreeList;

public partial class _Default : System.Web.UI.Page {
    protected override void OnInit(EventArgs e) {
        base.OnInit(e);
        InitTreeList(ASPxTreeList1);
    }

    protected void Page_Load(object sender, EventArgs e) {
        ASPxTreeList1.DataBind();
        (ASPxTreeList1 as IPostBackDataHandlerEx).ForceLoadPostData(Tree.ID, HttpContext.Current.Request.Params);
    }

    OleDbDataAdapter CreateDataAdapter() {
        string connectionString =
        @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Databases\Departments.mdb";
        OleDbConnection myConnection = new OleDbConnection(connectionString);
        string query =
        "SELECT [ID], [ParentID], [Department], [Budget], [Location] FROM [Departments]";
        return new OleDbDataAdapter(query, myConnection);
    }
    DataTable CreateDataTable(OleDbDataAdapter myAdapter) {
        DataTable dt = new DataTable();
        DataSet testData = new DataSet();
        myAdapter.Fill(testData);
        return testData.Tables[0];
    }
    void InitTreeList(ASPxTreeList tl) {
        tl.SettingsSelection.Recursive = true;
        tl.SettingsSelection.AllowSelectAll = true;
        tl.SettingsSelection.Enabled = true;
        tl.KeyFieldName = "ID";
        tl.ParentFieldName = "ParentID";
        tl.DataSource = CreateDataTable(CreateDataAdapter());
    }
}

VB.NET

Imports Microsoft.VisualBasic
Imports System
Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls
Imports System.Data.OleDb
Imports DevExpress.Web.ASPxTreeList

Public Partial Class _Default
    Inherits System.Web.UI.Page
    Protected Overrides Sub OnInit(ByVal e As EventArgs)
        MyBase.OnInit(e)
        InitTreeList(ASPxTreeList1)
    End Sub

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
         ASPxTreeList1.DataBind()
        (ASPxTreeList1 as IPostBackDataHandlerEx).ForceLoadPostData(Tree.ID, HttpContext.Current.Request.Params)
    End Sub

    Private Function CreateDataAdapter() As OleDbDataAdapter
        Dim connectionString As String = _
        "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Databases\Departments.mdb"
        Dim myConnection As OleDbConnection = New OleDbConnection(connectionString)
        Dim query As String = _
        "SELECT [ID], [ParentID], [Department], [Budget], [Location] FROM [Departments]"
        Return New OleDbDataAdapter(query, myConnection)
    End Function
    Private Function CreateDataTable(ByVal myAdapter As OleDbDataAdapter) As DataTable
        Dim dt As DataTable = New DataTable()
        Dim testData As DataSet = New DataSet()
        myAdapter.Fill(testData)
        Return testData.Tables(0)
    End Function
    Private Sub InitTreeList(ByVal tl As ASPxTreeList)
        tl.SettingsSelection.Recursive = True
        tl.SettingsSelection.AllowSelectAll = True
        tl.SettingsSelection.Enabled = True
        tl.KeyFieldName = "ID"
        tl.ParentFieldName = "ParentID"
        tl.DataSource = CreateDataTable(CreateDataAdapter())
    End Sub
End Class

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the DataSource 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#

aspxtreelist-how-to-implement-node-reordering-t604737/CS/NodeReordering/Default.aspx.cs#L17

{
    TreeList.DataSource = dataHelper.Data;
    TreeList.DataBind();

how-to-reload-grid-data-when-navigating-the-treelist-e934/CS/SyncWithGridOnUpdatePanel/Default.aspx.cs#L20

private void BindTreeList() {
    ASPxTreeList1.DataSource = GetData();
    ASPxTreeList1.KeyFieldName = "ID";

how-to-use-a-single-aspxpopupcontrol-for-the-entire-application-t501713/CS/T501713/WebForm2.aspx.cs#L39

    (sender as ASPxTreeList).ParentFieldName = "Parent";
    (sender as ASPxTreeList).DataSource = Enumerable.Range(0, 10).Select(i => new { Id = i, Name = "Name" + i, Parent = i % 3 }).ToList();
};

VB.NET

aspxtreelist-how-to-implement-node-reordering-t604737/VB/NodeReordering/Default.aspx.vb#L16

Protected Sub Page_Init(ByVal sender As Object, ByVal e As EventArgs)
    TreeList.DataSource = dataHelper.Data
    TreeList.DataBind()

how-to-reload-grid-data-when-navigating-the-treelist-e934/VB/SyncWithGridOnUpdatePanel/Default.aspx.vb#L22

Private Sub BindTreeList()
    ASPxTreeList1.DataSource = GetData()
    ASPxTreeList1.KeyFieldName = "ID"

how-to-use-a-single-aspxpopupcontrol-for-the-entire-application-t501713/VB/T501713/WebForm2.aspx.vb#L43

    TryCast(sender, ASPxTreeList).ParentFieldName = "Parent"
    TryCast(sender, ASPxTreeList).DataSource = Enumerable.Range(0, 10).Select(Function(i) New With {Key .Id = i, Key .Name = "Name" & i, Key .Parent = i Mod 3}).ToList()
End Sub