public void UpdateExtractFile()

Public Sub UpdateExtractFile

using DevExpress.DashboardCommon;
using DevExpress.DashboardWin;
using System.IO;
using System.Linq;
using System.Windows.Forms;

namespace ExtractDataSourceExample {
    public partial class Form1 : DevExpress.XtraEditors.XtraForm {
        public Form1() {
            InitializeComponent();
            dashboardViewer1.CustomizeDashboardTitle += DashboardViewer1_CustomizeDashboardTitle;
            dashboardViewer1.LoadDashboard("DashboardTest.xml");
        }

        delegate void SafeUpdate(string file);
        private void CreateExtractAndSave() {
            DataSourceCollection dsCollection = new DataSourceCollection();
            dsCollection.AddRange(dashboardViewer1.Dashboard.DataSources.Where(d => !(d is DashboardExtractDataSource)));
            foreach (var ds in dsCollection) {
                    DashboardExtractDataSource extractDataSource = new DashboardExtractDataSource();
                    extractDataSource.ExtractSourceOptions.DataSource = ds;

                    if (ds is DashboardSqlDataSource)
                        extractDataSource.ExtractSourceOptions.DataMember = ((DashboardSqlDataSource)(ds)).Queries[0].Name;

                    extractDataSource.FileName = Path.GetFullPath($"Extract_{ds.Name}.dat");
                    extractDataSource.UpdateExtractFile();
                    foreach (DataDashboardItem item in dashboardViewer1.Dashboard.Items)
                        if (item.DataSource == ds)
                            item.DataSource = extractDataSource;
            }
            dashboardViewer1.Dashboard.DataSources.RemoveRange(dsCollection);
            dashboardViewer1.Dashboard.SaveToXml("Dashboard_Extract.xml");
        }

        private void UpdateExtract() {
            dashboardViewer1.ReloadData();
            foreach (var ds in dashboardViewer1.Dashboard.DataSources.Where(d => d is DashboardExtractDataSource)) {
                ((DashboardExtractDataSource)ds).UpdateExtractFile();
            }
        }

        private async void UpdateExtractAsync() {
            await dashboardViewer1.UpdateExtractDataSourcesAsync(
                (fileName, result) => { 
                    OnDataReady(fileName); 
                },
                (fileName, result) => { 
                    MessageBox.Show($"File {fileName} updated "); 
                });
        }

        void OnDataReady(string fileName) {
            dashboardViewer1.Invoke(new SafeUpdate(UpdateViewer), new object[] { fileName });
        }
        void UpdateViewer(string fileName) {
            MessageBox.Show($"Data for the file {fileName} is ready ");
            dashboardViewer1.ReloadData();
        }

        private void DashboardViewer1_CustomizeDashboardTitle(object sender, CustomizeDashboardTitleEventArgs e) {
            DashboardToolbarItem itemUpdate = new DashboardToolbarItem((args) => UpdateExtract()) {
                Caption = "Update Extract Data Source",
            };
            e.Items.Add(itemUpdate);

            DashboardToolbarItem itemUpdateAsync = new DashboardToolbarItem((args) => UpdateExtractAsync()) {
                Caption = "Async Update Extract Data Sources",
            };
            e.Items.Add(itemUpdateAsync);

            DashboardToolbarItem itemSave = new DashboardToolbarItem((args) => CreateExtractAndSave()) {
                Caption = "Create Extract Data Source",
            };
            e.Items.Insert(0,itemSave);
        }
    }
}

Imports DevExpress.DashboardCommon
Imports DevExpress.DashboardWin
Imports System.IO
Imports System.Linq
Imports System.Windows.Forms

Namespace ExtractDataSourceExample
    Partial Public Class Form1
        Inherits DevExpress.XtraEditors.XtraForm

        Public Sub New()
            InitializeComponent()
            AddHandler dashboardViewer1.CustomizeDashboardTitle, AddressOf DashboardViewer1_CustomizeDashboardTitle
            dashboardViewer1.LoadDashboard("DashboardTest.xml")
        End Sub

        Private Delegate Sub SafeUpdate(ByVal file As String)
        Private Sub CreateExtractAndSave()
            Dim dsCollection As New DataSourceCollection()
            dsCollection.AddRange(dashboardViewer1.Dashboard.DataSources.Where(Function(d) Not (TypeOf d Is DashboardExtractDataSource)))
            For Each ds In dsCollection
                Dim extractDataSource As New DashboardExtractDataSource()
                extractDataSource.ExtractSourceOptions.DataSource = ds

                If TypeOf ds Is DashboardSqlDataSource Then
                    extractDataSource.ExtractSourceOptions.DataMember = DirectCast(ds, DashboardSqlDataSource).Queries(0).Name
                End If

                extractDataSource.FileName = Path.GetFullPath($"Extract_{ds.Name}.dat")
                extractDataSource.UpdateExtractFile()
                For Each item As DataDashboardItem In dashboardViewer1.Dashboard.Items
                    If item.DataSource Is ds Then
                        item.DataSource = extractDataSource
                    End If
                Next item
            Next ds
            dashboardViewer1.Dashboard.DataSources.RemoveRange(dsCollection)
            dashboardViewer1.Dashboard.SaveToXml("Dashboard_Extract.xml")
        End Sub

        Private Sub UpdateExtract()
            dashboardViewer1.ReloadData()
            For Each ds In dashboardViewer1.Dashboard.DataSources.Where(Function(d) TypeOf d Is DashboardExtractDataSource)
                CType(ds, DashboardExtractDataSource).UpdateExtractFile()
            Next ds
        End Sub

        Private Sub UpdateExtractAsync()
            dashboardViewer1.UpdateExtractDataSourcesAsync(
                Sub(fileName, result)
                    OnDataReady(fileName)
                End Sub,
                Sub(fileName, result)
                    MessageBox.Show($"File {fileName} updated ")
                End Sub)
        End Sub

        Private Sub OnDataReady(ByVal fileName As String)
            dashboardViewer1.Invoke(New SafeUpdate(AddressOf UpdateViewer), New Object() {fileName})
        End Sub
        Private Sub UpdateViewer(ByVal fileName As String)
            MessageBox.Show($"Data for the file {fileName} is ready ")
            dashboardViewer1.ReloadData()
        End Sub

        Private Sub DashboardViewer1_CustomizeDashboardTitle(ByVal sender As Object, ByVal e As CustomizeDashboardTitleEventArgs)
            Dim itemUpdate As New DashboardToolbarItem(Sub(args) UpdateExtract()) With {.Caption = "Update Extract Data Source"}
            e.Items.Add(itemUpdate)

            Dim itemUpdateAsync As New DashboardToolbarItem(Sub(args) UpdateExtractAsync()) With {.Caption = "Async Update Extract Data Sources"}
            e.Items.Add(itemUpdateAsync)

            Dim itemSave As New DashboardToolbarItem(Sub(args) CreateExtractAndSave()) With {.Caption = "Create Extract Data Source"}
            e.Items.Insert(0,itemSave)
        End Sub
    End Class
End Namespace

extractDataSource.FileName = Path.GetFullPath($"Extract_{ds.Name}.dat");
extractDataSource.UpdateExtractFile();
foreach (DataDashboardItem item in dashboardViewer1.Dashboard.Items)

dataExtract.Filter = "[ProductName] = 'Chai'";
dataExtract.UpdateExtractFile();
// Adds the Extract Data Source to the dashboard.

using (var ds = CreateExtractDataSource()) {
    ds.UpdateExtractFile();
}

extractDataSource.FileName = Path.GetFullPath($"Extract_{ds.Name}.dat")
extractDataSource.UpdateExtractFile()
For Each item As DataDashboardItem In dashboardViewer1.Dashboard.Items

dataExtract.Filter = "[ProductName] = 'Chai'"
dataExtract.UpdateExtractFile()
' Adds the Extract Data Source to the dashboard.

Using ds = CreateExtractDataSource()
    ds.UpdateExtractFile()
End Using