ASPxDashboard.CustomDataCallback Event
Fires when a round trip to the server has been initiated by a call to the client ASPxClientDashboard.PerformDataCallback method.
Namespace: DevExpress.DashboardWeb
Assembly: DevExpress.Dashboard.v24.1.Web.WebForms.dll
NuGet Package: DevExpress.Web.Dashboard
Declaration
Event Data
The CustomDataCallback event's data class is CustomDataCallbackEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| Parameter | Gets a string that contains specific information (if any) passed from the client side. Inherited from CallbackEventArgsBase. |
| Result | Gets or sets a string that contains specific information (if any) that needs to be passed to the client side for further processing. |
Remarks
The CustomDataCallback event allows any desired server-side processing to be performed, and any resulting required information to be passed to the client for further processing (if needed).
After the CustomDataCallback event has been processed on the server side, a result can be passed back to the client via the CallbackEventArgs.Result property. To receive the result on the client, handle the ASPxClientDashboard.CustomDataCallback event.
Example
This example demonstrates how to export a dashboard displayed in ASPxDashboard on the server side using the ASPxDashboardExporter class. The following API is used to implement this capability.
- The ASPxDashboard.CustomJSProperties server-side event is used to pass information about available dashboards to the client side.
- The ASPxClientDashboard.LoadDashboard method opens a selected dashboard.
- The ASPxClientDashboard.PerformDataCallback client-side method is used to pass the dashboard identifier and state to the server side. On the server side, the
ASPxDashboard.CustomDataCallbackevent is used to obtain and parse these values. - WebDashboardExporter.ExportToPdf is used to export the selected dashboard with the state passed from the client side.
using DevExpress.DashboardCommon;
using DevExpress.DashboardWeb;
using System;
using System.Collections.Generic;
using System.IO;
using System.Web.Hosting;
namespace ASPxDashboard_ServerExport {
public partial class Default : System.Web.UI.Page {
DashboardFileStorage fileStorage = new DashboardFileStorage("App_Data/Dashboards");
protected void Page_Load(object sender, EventArgs e) {
ASPxDashboard1.AllowExportDashboard = false;
ASPxDashboard1.SetDashboardStorage(fileStorage);
}
protected void ASPxDashboard1_CustomJSProperties(object sender, DevExpress.Web.CustomJSPropertiesEventArgs e){
List<string> dashboardIDs = new List<string>();
foreach (DashboardInfo dashboardInfo in ((IDashboardStorage)fileStorage).GetAvailableDashboardsInfo()) {
dashboardIDs.Add(dashboardInfo.ID);
}
e.Properties.Add("cpGetDashboardIDs", dashboardIDs);
}
protected void ASPxDashboard1_CustomDataCallback(object sender, DevExpress.Web.CustomDataCallbackEventArgs e) {
using (MemoryStream stream = new MemoryStream()) {
string selectedDashboardID = e.Parameter.Split('|')[0];
string dashboardStateJson = e.Parameter.Split('|')[1];
DashboardState dashboardState = new DashboardState();
dashboardState.LoadFromJson(dashboardStateJson);
DashboardPdfExportOptions pdfOptions = new DashboardPdfExportOptions();
pdfOptions.ExportFilters = true;
pdfOptions.DashboardStatePosition = DashboardStateExportPosition.Below;
string serverPath = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
if (!Directory.Exists(serverPath)) {
Directory.CreateDirectory(serverPath);
}
string dateTimeNow = DateTime.Now.ToString("yyyyMMddHHmmss");
string filePath = serverPath + "\\" + selectedDashboardID + "_" + dateTimeNow + ".pdf";
ASPxDashboardExporter exporter = new ASPxDashboardExporter(ASPxDashboard1);
exporter.ExportToPdf(selectedDashboardID, stream, new System.Drawing.Size(1920, 1080), dashboardState, pdfOptions);
SaveFile(stream, filePath);
e.Result = filePath;
}
}
private void SaveFile(MemoryStream stream, string path) {
var fileStream = File.Create(path);
stream.WriteTo(fileStream);
fileStream.Close();
}
}
}
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="ASPxDashboard_ServerExport.Default" %>
<%@ Register Assembly="DevExpress.Dashboard.v23.1.Web.WebForms, Version=23.1.13.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a"
Namespace="DevExpress.DashboardWeb" TagPrefix="dx" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div id="selectBox" style="float: left;"></div>
<div id="buttonContainer" style="float: left; margin-left: 150px;"></div>
<div style="position: absolute; left: 0; right: 0; top:50px; bottom:0;">
<dx:ASPxDashboard ID="ASPxDashboard1" runat="server" Width="100%" Height="100%" WorkingMode="Viewer"
ClientInstanceName="webDashboard"
OnCustomDataCallback="ASPxDashboard1_CustomDataCallback"
OnCustomJSProperties="ASPxDashboard1_CustomJSProperties">
<ClientSideEvents
BeforeRender="function(s, e) { onBeforeRender(s,e); }"
CustomDataCallback="function(s, e) { dashboardExportedSuccess(e); }"/>
</dx:ASPxDashboard>
</div>
</form>
</body>
</html>
<script type="text/javascript" src="<%= Page.ResolveClientUrl("~/Scripts/InitializeControls.js") %>"></script>
function onBeforeRender(s,e) {
var dashboardControl = s.GetDashboardControl();
$("#buttonContainer").dxButton({
text: "Export to PDF",
onClick: function (param) {
var selectedDashboardID = dashboardControl.getDashboardId();
var dashboardState = dashboardControl.getDashboardState();
var parameters = selectedDashboardID + "|" + dashboardState;
webDashboard.PerformDataCallback(parameters, null);
}
});
$("#selectBox").dxSelectBox({
dataSource: getDashboardIDs(),
value: getDashboardIDs()[0],
onValueChanged: function (param) {
dashboardControl.loadDashboard(param.value);
}
});
}
function getDashboardIDs() {
return webDashboard.cpGetDashboardIDs;
};
function dashboardExportedSuccess(args) {
DevExpress.ui.notify('A dashboard was exported to ' + args.result, 'success', 5000);
};
See Also