Last Updated: 24 May 2024 08:14 by Frank
Scheduled for 2024 Q3 (Aug)
Since Telerik UI for Blazor 6.0.0 if I have defined aggregates and I load the Grid's data with async method the data never loads in the Grid. 
Last Updated: 23 May 2024 20:35 by Alexey

The Editor is not showing its Value in the following scenario:

  • Using JSInterop in OnAfterRenderAsync
  • Setting the Editor Value in OnAfterRenderAsync and after the JSInterop call
  • Blazor Server app (seems to work in WebAssembly)

Possible workarounds are:

  • Set the Editor Value and call StateHasChanged() before using JSInterop in OnAfterRenderAsync, or
  • Add some small delay (for example, await Task.Delay(100); ) before using JSInterop.
Last Updated: 23 May 2024 17:49 by Justin
Created by: Justin
Comments: 2
Category: UI for Blazor
Type: Bug Report

When SelectOnFocus="true" is enabled on the NumericTextBox control, and a format (e.g., Format="N1") is set, the SelectOnFocus functionality does not select all text if the decimal value has no trailing digits. For instance, with the value 76, the text is not selected on focus, but with the value 76.1, the text is selected correctly.

<TelerikNumericTextBox @bind-Value="@DecimalValue" Format="N1" SelectOnFocus="true"/>

@code {
    private decimal DecimalValue = 76;


Steps to Reproduce:

  1. Add a NumericTextBox control to a Blazor Server application.
  2. Set SelectOnFocus="true".
  3. Set a format, e.g., Format="N1".
  4. Enter a value such as 76 (with no trailing digits after the decimal point).
  5. Focus on the NumericTextBox.

Expected Behavior: The entire text (in this case, 76.0) should be selected when the NumericTextBox gains focus.

Actual Behavior: The text is not selected when the NumericTextBox gains focus if the value has no trailing digits after the decimal point (e.g., 76). However, if the value includes trailing digits (e.g., 76.1), the text is selected as expected.

Last Updated: 23 May 2024 13:44 by ADMIN
Scheduled for 2024 Q3 (Aug)

When I change the date while I'm in the month view, the slot doesn't change to the newly calculated ItemsPerSlot value.

To reproduce, open the calendar and set the date to the 3rd of December: REPL link.

Last Updated: 23 May 2024 10:42 by ADMIN
Release 2024 Q2 (May)

I've made a simple blazor repl demo here:

As you can see, TotalCount is 10, and the current PageSize is also 10. When these values match, the value in the "items per page" dropdown isn't present. Select any other value, and it will be present (for 5, 20, 40). Come back to 10, and again, the value disappears.

Last Updated: 23 May 2024 08:11 by ADMIN
When you open a predefined dialog (in OnInitialized) from inside a modal window, the dialog appears behind the modal.
Last Updated: 23 May 2024 05:42 by ADMIN
Scheduled for 2024 Q3 (Aug)
The ZoomChanged event doesn't fire when the user clicks on the zoom in/out buttons or selects a new zoom level from the ComboBox.
Last Updated: 22 May 2024 13:00 by Nate

In this example.  Select a cell in column C.  Then double click on another cell in column C.  The unhandled exception will show up and a null reference exception is logged in the console.

The exception message is:

System.InvalidOperationException: TelerikValidationComponent requires a cascading parameter of type EditContext. You can use Telerik.Blazor.Components.TelerikValidationTooltip`1[System.String] inside a EditForm or TelerikForm.

Last Updated: 22 May 2024 12:58 by ADMIN
Created by: Tung
Comments: 1
Category: UI for Blazor
Type: Bug Report



Here is my demo DatePicker Demo

In Firefox, after I use the mouse to black all texts out, then DatePicker only selects the month field in the place holder. I expect to select all texts.

In Chrome or Edge, the DatePicker works as expected, after blacking texts out, it selects all texts in the place holder

Could you please check the issue?


Thanks and regards,


Last Updated: 22 May 2024 11:16 by Philip

When the user opens the DateTimePicker(Time step) or the TimePicker, which are bound to some value, and clicks directly the "Set" button, the pickers don't bind the displayed time value (pre-selected value). This behavior can be seen when the pickers have configured steps (e.g. Minute: "15", Year="10" etc.)

Steps To Reproduce

  1. Open link -
  2. Open the TimePicker
  3. Click the "Set" button, to set the pre-selected value
Last Updated: 21 May 2024 15:31 by ADMIN


 when using SetStateAsync(), OnRead is called ok, but loading indicator is not presented as usual.

How to reproduce:

1. button = loading data by SetStateAsync(), no progress indicated.

2. button = loading data throught rebind, is ok

demo in repl

demo is based on

Expected: same behavior as by button 2.  -> Rebind()->OnRead()...loading progress


Last Updated: 21 May 2024 14:15 by ADMIN

When filtering or editing a Grid with enum data, the Name property of their Display parameter is respected.

However, in the initial view mode of the Grid the Name property is not applied and the enum values are rendered regardless of whether or not their Display parameter has a Name property defined.





In the meantime, a workaround you might try is to create a custom method to check whether Display attribute is defined and get and display its Name property, otherwise display the Enum's member name.

You can then use a Template for the column that uses enum data, cast its context to the model you are using and invoke the method on the field containing the enum. The sample below demonstrates how you can achieve this.

@using System.ComponentModel.DataAnnotations
@using System.Reflection

<TelerikGrid Data=@MyData EditMode="@GridEditMode.Inline" Pageable="true" Height="500px"
             OnUpdate="@UpdateHandler" FilterMode="@GridFilterMode.FilterRow">
        <GridColumn Field=@nameof(SampleData.ID) Editable="false" Title="ID" />
        <GridColumn Field=@nameof(SampleData.Name) Title="Name" />
        <GridColumn Field=@nameof(SampleData.Role) Title="Position">       
                    var currentEmployee = context as SampleData;
                    var currentRole = GetDisplayName(currentEmployee.Role);                        

            <GridCommandButton Command="Save" Icon="save" ShowInEdit="true">Update</GridCommandButton>
            <GridCommandButton Command="Edit" Icon="edit">Edit</GridCommandButton>

@code {
    //custom method to check whether Display attribute is defined and get and display its Name property, otherwise display the Enum's member name
    public string GetDisplayName(Enum val)
        return val.GetType()
                  ?? val.ToString();

    public void UpdateHandler(GridCommandEventArgs args)
        SampleData item = (SampleData)args.Item;

        //update the view-model
        var index = MyData.FindIndex(i => i.ID == item.ID);
        if (index != -1)
            MyData[index] = item;

        //perform actual data source operations here

    //model and dummy data generation
    public class SampleData
        public int ID { get; set; }
        public string Name { get; set; }
        public Role Role { get; set; }

    public enum Role
        [Display(Name = "Manager")]
        [Display(Name = "Employee")]
        [Display(Name = "Contractor")]

    public List<SampleData> MyData { get; set; }

    protected override void OnInitialized()
        MyData = new List<SampleData>();

        for (int i = 0; i < 50; i++)
            MyData.Add(new SampleData()
                ID = i,
                Name = "name " + i,
                Role = (Role)(i % 3) // just some sample to populate initial values for the enum

Last Updated: 21 May 2024 08:20 by George

See below repl

The first dropdown is populated correctly, it is not in a FormItem or Template

The second one, populated in the same way but inside a FormItem context does not show the data, it only redraws and shows data when entering another control i.e. the other working dropdown.

This was previously working when the application was using .net 6 and Telerik 3.6.1
It has since been updated to .net 8 and Telerik 5.1.1

What is the correct way to populate this?
Can you provide more information?


Last Updated: 20 May 2024 15:39 by ADMIN
Scheduled for 2024 Q3 (Aug)
According to the Rendering Changes in 6.0.0 article, "k-level-0" CSS class should be added to the "li.k-drawer-item" element. This class, however, is never added.
Last Updated: 20 May 2024 13:23 by Shannon

When the user enters a value, clicks out of the Masked Textbox and then back into it, the cursor is placed at the beginning of the input rather than at the end of the value.

This issue only happens when:

  • The MaskedTextBox does not have a mask specified.
  • The MaskedTextBox does not have an initial value.


Last Updated: 16 May 2024 16:24 by Tung

When dragging the mouse to select the whole input value, only the first segment on the left remains selected after releasing the mouse. The issue is reproducible in the DatePicker demo once you select a date. Video:

The problem is only reproducible in Firefox, the whole input is properly selected in Chrome and Edge.

Last Updated: 15 May 2024 13:53 by Juan Angel
If the data contains special double values (such as double.NaN or double.PositiveInfinity) and the Grid uses aggregates, it throws with:

Error: System.OverflowException: Value was either too large or too small for a Decimal.

Last Updated: 15 May 2024 08:33 by Ben
The IsEntityFrameworkProvider method in the DataSource package returns false when the provider is Entity Framework Core. 
Last Updated: 15 May 2024 08:26 by ADMIN



 it seems that grid.GetState() and FilterDescriptors, contains +1 "dummy" object.

- If it is by design, ok, BUT then, how to bind this filter descriptor to the ie TelerikFilter? = It displays that dummy object as it is, and confusing end users. Or how to "identify 100%" that is some kind of dummy value to be trashed?

How to reproduce:

1 run the repl demo

2 put "a" into the first colum(Name) filter

3 click button and observe the content of filter descriptors(serialized below the grid - RED is wrong, Green is expected as ok)

similar, but not the same(iam came from here):


Thanks for the tip, clarification, or removing that redundant values.

Last Updated: 13 May 2024 14:11 by SturmA

The Grid exits edit mode when expanding or collapsing rows in a hierarchy scenario. This only happens when OnStateChanged is set.

Test page that reproduces the behavior:

1 2 3 4 5 6