29 Jan to 05 Feb 2026: highlights of the new online resources that we published last week.

Blog: https://www.telerik.com/blogs/building-rag-aspnet-core
Summary: Learn how to implement a Retrieval-Augmented Generation (RAG) pipeline in ASP.NET Core with C#: ingest and chunk documents, generate embeddings via OpenAI or Azure OpenAI, store them in a vector database, run similarity search, and feed retrieved context to an LLM to answer user prompts. The article provides end-to-end C# code for services and controllers, dependency injection and configuration of API keys, and a minimal chat interface so you can run a local RAG Web API and UI.

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19 Jan to 26 Jan 2026: highlights of the new online resources that we published last week.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/grid-use-grid-as-client-template
Summary: Learn how to render a Kendo UI Grid inside a Telerik UI for ASP.NET Core Grid column using a ClientTemplate: output a per-row placeholder with a unique id (for example, via kendo.guid()) and initialize the child grid in the parent grid’s dataBound handler using the current row’s data. The article shows how to pass the row key to the child grid’s DataSource, prevent duplicate initialization, and dispose nested grids on rebind to avoid memory leaks.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/tooltip-refresh-with-dynamic-content
Summary: To keep a Kendo UI Tooltip for ASP.NET Core in sync with dynamic content and targets (after AJAX/partial updates or data-bound component renders), initialize it on a stable container and use the filter option with a content callback, or update the content via setOptions in the show event. The article shows how to attach the tooltip to newly added elements and render up-to-date content without re-initialization, plus when to destroy and re-initialize as a fallback in Grid/list or SPA scenarios.

Blog: https://www.telerik.com/blogs/getting-the-right-row-on-the-screen-in-the-kendo-grid
Summary: Learn how to programmatically bring a specific row into view in the Kendo UI Grid and optionally select it, even when paging, sorting, filtering, or virtual scrolling is enabled. The article shows how to resolve a data item to its correct DOM row via the item’s uid (e.g., grid.tbody.find("tr[data-uid='...']")) and then scroll the grid’s content to that row (scrollTop or scrollIntoView), with guidance on triggering the logic at the right time using dataBound.

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12 Jan to 19 Jan 2026: highlights of the new online resources that we published last week.

Blog: https://www.telerik.com/blogs/building-resilient-apis-retry-pattern
Summary: You’ll learn how to implement the retry pattern for API clients and services—when to retry transient failures and when to fail fast. The article provides .NET examples using HttpClientFactory and Polly to apply bounded retries with exponential backoff and jitter, target idempotent operations, and handle retryable HTTP status codes (408, 429, 500, 502, 503, 504), with practical guidance on timeouts, cancellation tokens, and telemetry.

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05 Jan to 12 Jan 2026: highlights of the new online resources that we published last week.

Article: https://www.telerik.com/aspnet-core-ui/documentation/html-helpers/diagrams-and-maps/map/azure-tiles
Summary: Learn how to render Azure Maps tiles in the Telerik UI for ASP.NET Core Map by adding a tile layer with the Azure Maps Tile API URL template. You configure the layer’s UrlTemplate with {zoom}/{x}/{y}, provide your Azure Maps subscription key and the tilesetId (for example microsoft.base.road or microsoft.imagery), and set the required attribution. The article uses the Map HTML Helper and TileSource options to control tile size, zoom levels, and other layer settings.

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29 Dec to 05 Jan 2026: highlights of the new online resources that we published last week.

Blog: https://www.telerik.com/blogs/whats-new-apis-net-10-real-improvements
Summary: This article breaks down what's new in .NET 10 APIs, focusing on practical Base Class Library improvements you can apply immediately. It covers updates across collections, spans/UTF-8, I/O and networking, date/time, cryptography, diagnostics, and threading, with concise examples and notes on performance, memory, and reliability. Use it to plan adoption in existing projects by mapping old patterns to new overloads and helpers that reduce allocations and simplify async and data processing.

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22 Dec to 29 Dec 2025: highlights of the new online resources that we published last week.

Blog: https://www.telerik.com/blogs/whats-new-net-10-aspnet-core
Summary: This article walks you through what’s new in ASP.NET Core for .NET 10 and how to adopt the changes, with focused code examples and notes on breaking changes to help you plan upgrades. It covers updates across hosting and Kestrel, routing and minimal APIs, Blazor, authentication/authorization and security, caching and performance, and provides practical migration guidance for moving to .NET 10.

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15 Dec to 22 Dec 2025: highlights of the new online resources that we published last week.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/grid-ai-integration
Summary: Learn how to add AI integration to the Telerik UI for ASP.NET Core Grid by invoking OpenAI or Azure OpenAI to analyze grid data and display the response in a dialog. You will add a custom toolbar command, collect selected rows and column metadata on the client, call an ASP.NET Core controller that wraps the OpenAI REST API, and render the result in the UI. The article covers configuring OpenAI/Azure OpenAI, prompt construction, server-side API key handling, and basic error handling.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/chart-ai-integration
Summary: Implement AI-assisted analysis for the Telerik/Kendo UI for ASP.NET Core Chart by extracting series data, sending it to an AI provider (e.g., OpenAI or Azure OpenAI) from a secure server-side controller, and rendering the generated summary in a UI element (such as a Dialog). The article provides Razor and controller examples using HttpClient and environment-stored API keys, plus guidance on prompt design, minimizing shared data, and keeping keys off the client.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/editor-ai-integration
Summary: Learn how to integrate OpenAI or Azure OpenAI with the Telerik UI for ASP.NET Core Editor by adding a custom toolbar menu that posts the current content and selected action to a server-side ASP.NET Core endpoint, then inserts or replaces the text with the AI response. The article provides Editor configuration, JavaScript, and controller code that calls the Chat Completions API with prompt templates for rewrite, summarize, translate, and grammar fixes, keeping the API key on the server.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/scheduler-ai-integration
Summary: Learn how to integrate the Telerik UI for ASP.NET Core Scheduler with an LLM-backed AI workflow to create, edit, translate, or summarize events from natural language. You’ll add the Kendo AI Prompt to the Scheduler UI, handle its execute event on the client, and implement a C# endpoint that calls an LLM (e.g., OpenAI or Azure OpenAI) and maps the JSON response to Scheduler events. The article includes end-to-end wiring, request/response shaping, and safe parsing to update the Scheduler data source.

Article: https://www.telerik.com/aspnet-core-ui/documentation/html-helpers/data-management/grid/smart-grid/smart-extensions
Summary: This article explains how to use Smart Extensions for the Telerik UI for ASP.NET Core Grid (Smart Grid) to apply preset configuration through extension methods on the Grid HtmlHelper. It covers setup (package and namespace), the available extensions and what they enable (such as filtering, sorting, paging, toolbars, commands, and column configuration), and how to customize or override defaults when composing Smart extensions with your own Grid settings.

Blog: https://www.telerik.com/blogs/managing-content-security-telerik-aspnet-core-applications
Summary: This article shows you how to add and enforce a Content Security Policy (CSP) in ASP.NET Core applications that use Telerik UI for ASP.NET Core, including setting security headers via middleware. It details the CSP directives and allowances required by the components—script-src, style-src, img-src, font-src, connect-src, worker-src, and support for blob: and data: URLs for features like file export—and how to use nonces/hashes and CSP‑compatible Telerik/Kendo assets to avoid 'unsafe-inline' and 'unsafe-eval'. You also get copy‑paste policy examples and troubleshooting guidance for scenarios such as CDN-hosted resources, PDF/Excel export, and WebSocket/SignalR connections.

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24 Nov to 01 Dec 2025: highlights of the new online resources that we published last week.

Blog: https://www.telerik.com/blogs/securing-apps-telerik-ui-aspnet-core-otp-control
Summary: You’ll implement one-time passcode (OTP/TOTP) verification in an ASP.NET Core app using the Telerik UI for ASP.NET Core OTP control, from configuring the control in Razor views to wiring server-side validation with ASP.NET Core Identity or a TOTP library. The article covers UX and security details—auto-advancing digit inputs, paste and accessibility, handling expiration and retries, and enforcing server-only validation, rate limiting, and secure secret storage—to build a reliable multi-factor authentication flow.

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17 Nov to 24 Nov 2025: highlights of the new online resources that we published last week.

Article: https://www.telerik.com/aspnet-core-ui/documentation/knowledge-base/chat-ai-integration
Summary: Integrate the Telerik UI for ASP.NET Core Chat with OpenAI or Azure OpenAI by handling the Chat send event, forwarding user messages to a server-side controller that calls the Chat Completions API, and returning the assistant’s reply as a Chat message. The article walks you through the Razor setup, controller/action implementation, secure API key handling, request/response models, role mapping (user/assistant), and basic error handling.

Blog: https://www.telerik.com/blogs/real-time-data-updates-telerik-ui-net-maui-grid
Summary: Learn how to implement real-time data updates in the Telerik UI for .NET MAUI Grid by binding to an ObservableCollection and models that implement INotifyPropertyChanged, so item additions/removals and per-cell changes propagate instantly. The article shows a timer-driven update loop and how to marshal background changes onto the UI thread, with practical guidance to keep frequent updates responsive.

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10 Nov to 17 Nov 2025: highlights of the new online resources that we published last week.

Article: https://www.telerik.com/aspnet-core-ui/documentation/ai-components-and-features
Summary: This article documents the AI Prompt and AI Chat components in Telerik UI for ASP.NET Core and shows you how to configure Tag/HTML Helpers and connect them to OpenAI or Azure OpenAI through ASP.NET Core endpoints. It covers setup, provider configuration, client/server APIs, streaming responses, attachments, context and message history, and content safety basics to help you implement AI features in your application.

Article: https://www.telerik.com/aspnet-core-ui/documentation/html-helpers/diagrams-and-maps/diagram/binding
Summary: You will bind the Telerik ASP.NET Core Diagram HTML Helper to your data so shapes and connections are generated from your schema. Configure DataSource and ConnectionsDataSource with model field mappings (Id, Text, X/Y for shape position; From/To for connections) and transport actions for server-side CRUD. The examples show remote binding, positioning, and handling data-bound events.

Article: https://www.telerik.com/aspnet-core-ui/documentation/html-helpers/diagrams-and-maps/diagram/razor-pages
Summary: This article shows how to use the ASP.NET Core Diagram HtmlHelper in Razor Pages: configure separate DataSources for shapes and connections with AJAX transport to page handlers (via Url.Page), map model fields (Id, From, To), and include the required Kendo UI scripts and styles. It provides .cshtml and PageModel code for Read, Create, Update, and Destroy operations and demonstrates adding anti-forgery tokens to the requests.

Feel free to check them out and share your thoughts!

The Telerik Team

1. Is it hard to understand the version numbers of our releases? If yes, what makes them hard to understand them?

2. Would semantic versioning (SemVer) of our releases make it easier to understand our version numbers and what's behind them?

3. If we go with SemVer, we might need to start with version 3000.0.0 as we currently use 2022.x.x. Please share your thoughts about this approach and ideas for what number versioning would work best for you.

Hi Team,

In our ASP.Net Core MVC project we are using the Telerik Feed for automatic package restoration which work fine by setting up the Username and Password in the nuget.config file inside the %AppData% Folder(C:\Users\-----\AppData\Roaming\NuGet  present inside windows), but when we try to deploy build into the server Nuget package restore is failing. May I expect any assistance on this or any steps are we missing which we need to follow to get restoration happen properly on the server.

I have some quick questions around the new license key requirements for the UI for ASP.NET MVC, UI for ASP.NET Core and Reporting modules.

I understand from the FAQ that each licensed developer will have their own separate license key.  We build the project on a separate build server, and package it into an installer, and then customers who self host run our installer to deploy the application.  Is there a license key that needs to be part of the deployment package, and if so, what key is that, when does it expire, and what happens when it expires?  

What I want to ensure 100% is that we don't have a situation where a customer *has* to deploy or upgrade their version of our software, even if we ever discontinue our subscription.  I'm fine with developers needing to update license keys on development environments, and I'm fine with customer production environments needing a new license key *if* they are deploying a new version of our software that includes an updated version of Telerik.  But it is not OK for my use case if there's a situation where customer production environments that are on an old version of our software with no plans to upgrade will stop working or show watermarks and require an update to fix.

I appreciate any clarification around this topic, or a shove in the right direction to any documentation that makes this clear.

How do use the Loader as a Loading Container so it covers the whole UI with a transparent overlay 

@(Html.Kendo().Loader()
    .Name("loader")
    .Size(LoaderSize.Large)
    .Type(LoaderType.ConvergingSpinner)
    )

Hello,

I can't seem to find a component for asp.net core that will just rotate images on a home page for example. Am I missing something? What component will do this?

Thanks

Closed

I was tasked at my company with implementing custom parameter editors in order to dynamically hide parameter depending on whether they should be available for use or not. I first followed this tutorial to create the custom parameter editors and the corresponding HTML5 Widget. Once I did that, I tried integrating the custom parameter edtiors into a HMTL5 Report Viewer using the ASP.NET Core 8 tutorial (links here, here, here) but after building both the REST service project and the HTML5 viewer, whenever I run the app, I simply land on a blank localhost page leading to Microsoft Tutorials on building NET Core apps. I have tried all available troubleshooting & looked at documentation but I have no idea how to move forward. I have double checked that I followed the tutorials correctly and still no progress. I am using Telerik Report Desginer R3 2020, Visual Studio 2022, .Net 8. Attached below is the code for the program.cs, appsettings.json, reportscontroller.cs, and index.html

AppSettings.json (Rest Project)

{
    "Logging": {
        "LogLevel": {
            "Default": "Information",
            "Microsoft.AspNetCore": "Warning"
        }
    },
    "AllowedHosts": "*",
    "ConnectionStrings": {
        "Telerik.Reporting.Examples.CSharp.Properties.Settings.TelerikConnectionString": "Data Source =.\\SQLEXPRESS; Initial Catalog=AdventureWorks; Intgrated Security = true"
    }
    
}

namespace TopLevelStatements.Controllers
{
    using System.Net;
    using System.Net.Mail;
    using Microsoft.AspNetCore.Mvc;
    using Telerik.Reporting.Services;
    using Telerik.Reporting.Services.AspNetCore;

    [Route("api/[controller]")]
    [ApiController]
    public class ReportsController : ReportsControllerBase
    {
        public ReportsController(IReportServiceConfiguration reportServiceConfiguration)
        : base(reportServiceConfiguration)
        {
        }

        protected override HttpStatusCode SendMailMessage(MailMessage mailMessage)
        {
            throw new System.NotImplementedException("This method should be implemented in order to send mail messages");

            // using (var smtpClient = new SmtpClient("smtp01.mycompany.com", 25))
            // {
            //     smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
            //     smtpClient.EnableSsl = false;
            //     smtpClient.Send(mailMessage);
            // }
            // return HttpStatusCode.OK;
        }
    }
}

using Microsoft.Extensions.DependencyInjection.Extensions;
using Telerik.Reporting.Services;
using Telerik.Reporting.Cache.File;


var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddRazorPages();
builder.Services.AddControllers().AddNewtonsoftJson();

// Configure dependencies for ReportsController.
builder.Services.TryAddSingleton<IReportServiceConfiguration>(sp =>
    new ReportServiceConfiguration
    {
        // The default ReportingEngineConfiguration will be initialized from appsettings.json or appsettings.{EnvironmentName}.json:
        ReportingEngineConfiguration = sp.GetService<IConfiguration>(),
        // In case the ReportingEngineConfiguration needs to be loaded from a specific configuration file, use the approach below:
        //ReportingEngineConfiguration = ResolveSpecificReportingConfiguration(sp.GetService<IWebHostEnvironment>()),
        HostAppId = "ReportingNet6",
        Storage = new FileStorage(),
        ReportSourceResolver = new UriReportSourceResolver(System.IO.Path.Combine(sp.GetService<IWebHostEnvironment>().ContentRootPath, "Reports"))
    });

builder.Services.AddCors(corsOption => corsOption.AddPolicy(
    "ReportingRestPolicy",
    corsBuilder =>
    {
        corsBuilder.AllowAnyOrigin()
            .AllowAnyMethod()
            .AllowAnyHeader();
    }
));


var app = builder.Build();

// Configure the HTTP request pipeline.
if (!app.Environment.IsDevelopment())
{
    app.UseExceptionHandler("/Error");
    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
    app.UseHsts();
}

app.UseHttpsRedirection();
app.UseStaticFiles();

app.UseRouting();

app.UseEndpoints(endpoints =>
{
    endpoints.MapRazorPages();
    endpoints.MapControllers();
    //...
});

app.UseStaticFiles();

app.UseAuthorization();

app.MapRazorPages();

app.UseCors("ReportingRestPolicy");

app.Run();

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title>Telerik HTML5 Report Viewer Demo in ASP.NET Core in .NET 5</title>
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale-1, maximum-scale=1" />
    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
    <link href="https://kendo.cdn.telerik.com/2020.3.1118/styles/kendo.common.min.css" rel="stylesheet" />
    <link href="https://kendo.cdn.telerik.com/2020.3.1118/styles/kendo.blueopal.min.css" rel="stylesheet" />
    <script src="https://localhost:44320/api/reports/resources/is/telerikReportViewer"></script>
    <style>
        #reportViewer1 {
            position: absolute;
            left: 5px;
            right: 5px;
            top: 50px;
            bottom: 5px;
            overflow: hidden;
            font-family: verdana, Arial;
    </style>
</head>
<body>
    <div id="reportViewer1">
        loading...
    </div>
    <script>
        $(document).ready(function () {
            $("#reportViewer1")
                .telerik_ReportViewer({
                    serviceurl: "https://localhost:44320/api/reports/", reportSource: {
                    },
                    report: "Barcodes Report.trdp", parameters: {}
viewMode: telerikReportViewer.ViewModes.INTERACTIVE, scaleMode: telerikReportViewer.ScaleModes.SPECIFIC, scale: 1.0,
                    enableAccessibility: false,
                    sendEmail: enabled: true }
});
});</script>
</body>
</html>