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Values clearing from multiselect UI, but still sent to controller in a custom grid edit

I have a grid with custom editors and they are bound to the grid as such.

columns.Bound(x => x.Parent).EditorTemplateName("ParentEditor").ClientTemplate("#= Parent === undefined || Parent === null ? '' : parentTemplate(Parent)#");
columns.Bound(x => x.Child).EditorTemplateName("ChildEditor").ClientTemplate("#= Child === undefined || Child === null ? '' : childTemplate(Child)#");

The two editor templates look like this:

@model List<ParentViewModel>  
@(Html.Kendo()  
     .MultiSelectFor(m => m)  
     .DataTextField("Name")  
     .DataValueField("Id")  
     .Placeholder("Select one or more parents")  
     .AutoBind(true)  
     .TagMode(MultiSelectTagMode.Multiple)   
     .DataSource(source =>  
     {  
         source  
         .Read(read =>  
         {  
             read.Action("GetParent", "Lookup");  
         });  
     })  
     .Events(events => events.Change("onParentChange"))  
)  


@model List<ChildViewModel>
@(Html.Kendo()
      .MultiSelectFor(m => m)
      .DataTextField("Name")
      .DataValueField("Id")
      .Placeholder("Select one or more children")
      .AutoBind(true)
      .TagMode(MultiSelectTagMode.Multiple)
      .DataSource(source =>
      {
          source
          .Read(read =>
          {
              read.Action("GetChild", "Lookup").Data("getCurrentParents");
          })
          ;
      })
)

The UI is properly populating when the grid loads and looks like this:

Coumn Parent|Column Child
A           |A1
B           |B1, B2

When the user edits the row and removes item B from Column Parent, this code is invoked (which I got from Kendo UI Snippet | Kendo UI Dojo)

function onParentChange(e) {
    var selectedonParentChange = this.value();
    let dataItems = e.sender.dataItems();

	var multiSelect = $("#Child").data("kendoMultiSelect");
	var value = multiSelect.value();
	multiSelect.dataSource.filter(getFilterObj(dataItems));
	multiSelect.dataSource.filter({});  // Adding or removing has no effect
    multiSelect.refresh();
	multiSelect.value(value);
	console.log("Second value: " + multiSelect.value());
    var dataSource = multiSelect.dataSource;
    dataSource.read();
}

function getFilterObj(dataItems){
  let filtObj = {
    logic: "or",
    filters: [],
  };

  if(dataItems.length > 0){
    for (var i = 0; i < dataItems.length; i++) {
      filtObj.filters.push({
        field: "ParentId",
        operator: "eq",
        value: dataItems[i].Id
      });
    }
  } else {
    filtObj.filters.push({
        field: "ParentId",
        operator: "eq",
        value: ""
      });
  }

  return filtObj;
}

After the code runs, the UI looks like this:
Coumn Parent|Column Child
A           |A1

So far so good.  The problem is that when the user hits save this ends up on the Network in the form data:

Parent[0].Id: ParentIdA
Parent[0].Name: A
Child[0].Id: ChildId1
Child[0].Name: A1
Child[0].ParentId: ParentIdA
Child[1].Id: ChildId2
Child[1].Name: B1
Child[1].ParentId: ParentIdB
Child[2].Id: ChildId3
Child[2].Name: B2
Child[2].ParentId: ParentIdB
Although B1 and B2 no longer display in the UI, they are still being sent to the controller when the item is saved.  I'm not sure how to prevent them from being sent when they are no longer in the UI.

Kendo Version: 2024.4.1112
Editor
Grid
MultiSelect
Eyup
Telerik team
 answered on 06 May 2025
1 answer
278 views
License Key Question

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.

General Discussions
Eyup
Telerik team
 answered on 06 May 2025
1 answer
68 views
Radedit error - System.Security.Cryptography.CryptographicException

I have some (9) ASPX pages with RadEdit controls in my application.
Since installing the asp.net Ajax version R3 2025 and 2025.1.211 dev hotfix (from a much older version) I'm getting an error whenever IIS tries to send me any of those pages with RadEdit (I can remove the RadEdit control and get the page - without the edit area, but if I put it back, the error returns).
The full error is:
03/04/2025 15:34:02 19: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Security.Cryptography.CryptographicException: The cryptographic operation has failed!
   at Telerik.Web.UI.CryptoExceptionThrower.ThrowGenericCryptoException[T]()
   at Telerik.Web.UI.CryptoExceptionThrower.ThrowIfFails[T](Func`1 function)
   at Telerik.Web.UI.Common.HmacEnabledCryptoService.Encrypt(String input)
   at Telerik.Web.Dialogs.DialogParametersSerializer.Serialize()
   at Telerik.Web.UI.DialogDefinition.get_SerializedParameters()
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, BindingFlags invokeAttr, Binder binder, Object[] index, CultureInfo culture)
   at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, Object[] index)
   at Telerik.Web.UI.DialogDefinitionConverter.Serialize(Object obj, JavaScriptSerializer serializer)
   at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat, MemberInfo currentMember)
   at System.Web.Script.Serialization.JavaScriptSerializer.SerializeDictionary(IDictionary o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat)
   at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValueInternal(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat, MemberInfo currentMember)
   at System.Web.Script.Serialization.JavaScriptSerializer.SerializeValue(Object o, StringBuilder sb, Int32 depth, Hashtable objectsInUse, SerializationFormat serializationFormat, MemberInfo currentMember)
   at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat)
   at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, SerializationFormat serializationFormat)
   at Telerik.Web.UI.RadDialogOpener.DescribeComponent(IScriptDescriptor descriptor)
   at Telerik.Web.UI.RadWebControl.Telerik.Web.IControl.DescribeComponent(IScriptDescriptor descriptor)
   at Telerik.Web.UI.ScriptRegistrar.GetScriptDescriptors(Control control)
   at Telerik.Web.UI.RadWebControl.GetScriptDescriptors()
   at Telerik.Web.UI.RadWebControl.System.Web.UI.IScriptControl.GetScriptDescriptors()
   at System.Web.UI.ScriptControlManager.RegisterScriptDescriptors(IScriptControl scriptControl)
   at Telerik.Web.UI.RadWebControl.RegisterScriptDescriptors()
   at Telerik.Web.UI.RadWebControl.Render(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
   at Telerik.Web.UI.RadEditor.RenderContents(HtmlTextWriter writer)
   at System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer)
   at Telerik.Web.UI.RadWebControl.Render(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
   at Telerik.Web.UI.RadPageView.RenderContents(HtmlTextWriter writer)
   at System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
   at Telerik.Web.UI.RadWebControl.RenderContents(HtmlTextWriter writer)
   at System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer)
   at Telerik.Web.UI.RadWebControl.Render(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer)
   at System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer)
   at System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
   at System.Web.UI.Page.Render(HtmlTextWriter writer)
   at System.Web.UI.Adapters.ControlAdapter.Render(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
   at Telerik.Web.UI.RadAjaxControl.RenderPageInAjaxMode(HtmlTextWriter writer, Control page)
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
   at System.Web.UI.Page.Render(HtmlTextWriter writer)
   at System.Web.UI.Adapters.ControlAdapter.Render(HtmlTextWriter writer)
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

 

Can anyone help or advise on what may be causing this?

Editor
Anislav
Top achievements
Rank 6
Silver
Bronze
Bronze
 answered on 05 Apr 2025
1 answer
101 views
Download an Azure blob container subfolder to a listview
I have the listview code for downloading the blob container. But I need to only get a subfolder in the container, not the whole thing. Is there a way to add the variable for the subfolder or should I structure the data in Azure differently and create a new container instead of using subfolders in one container?
public static async Task<List<string>> GetUploadedImages(AzureStorageConfig _storageConfig)
{
    List<ImageViewModel> images = new List<ImageViewModel>();

    // Create BlobServiceClient from the account URI
    BlobServiceClient blobServiceClient = new BlobServiceClient(_storageConfig.ConnectionString);

    // Get reference to the container
    BlobContainerClient container = blobServiceClient.GetBlobContainerClient(_storageConfig.ImageContainer);
    

    if (container.Exists())
    {
        var data = container.GetBlobs();
        foreach (BlobItem blobItem in container.GetBlobs())
        {
            images.Add(container.Uri + "/" + blobItem.Name);
        }
    }

    return await Task.FromResult(images);
}

ListView
Anislav
Top achievements
Rank 6
Silver
Bronze
Bronze
 answered on 05 Apr 2025
1 answer
37 views
Show values on chart for pdf export

Hy,

I have the following graph that displays the values ​​when I hover over the column with the mouse:

With the "PDF Export" button highlighted in yellow I export the graph to PDF using the chart API: https://demos.telerik.com/aspnet-core/chart-api/pdf-export

Attached you can find the export in pdf that is created.

How can I display the values ​​of the two series in the pdf file?

Thanks for any help

Chart
Eyup
Telerik team
 answered on 04 Apr 2025
2 answers
40 views
How can I enable a standard html Select as a custom tool in the Editor in Kendo for Asp.Net Core?
I'm trying to add a standard html Select element as a custom toolbar item in the Editor. I was able to make this work up through Kendo for Asp.Net Core version 2024.Q4. Now in version 2025.Q1 the Select does not respond to clicking. A click doesn't drop down the Select so the user can choose an Option item. I added an onclick event handler, and the click event is registering, but it does not open the Select. The documentation doesn't give any reason why this should not work. The Select element and its Options look fine in the page. Any suggestions?
        //Add a dropdown tool for inserting symbols.
        string selectTitle = "Select a symbol to insert";
        //Standard html select.
        //Cannot find a way to use an html Select in Kendo 2025Q1. This worked in Kendo 2024.Q4,
        // after removing the 'ref-toolbar-tool' attribute from the div preceding the Select.
        string toolNameSelect = $"insertSymbol-{EditorIdClean}";
        string dropdownNameSelect = $"symbolSelect_{EditorIdClean}";
        string symbolSelect = $"<label for='{dropdownNameSelect}' class='visually-hidden'>Symbol:</label>" +
            $"<select id='{dropdownNameSelect}' " +
            $"title='{selectTitle}' " +
            $"aria-label='{selectTitle}' " +
            "style='width:150px' " +
            "onclick='testSymbolSelect(this)' " + //The click event is registered * the alert appears.
            "onchange='InsertSymbolSelect(this)' " +
            ">" +
            $"{symbolHtmlSelectOptions()}" +
            $"</select>";
        toolFactories.Add(tools => tools
            .CustomTemplate(x => x
                .Name(toolNameSelect)
                .Tooltip(selectTitle)
                .Template(symbolSelect)
            ));

Editor
Toolbar
Mihaela
Telerik team
 answered on 03 Apr 2025
1 answer
51 views
Help with customizing grid's filter menus

I'm currently redesigning the filter menus in our MVC ASP.NET Core project. As of now, they all have the default menu:

I would like to customise the menus according to the columns' data types - have date range pickers for dates, a slider from min to max value for numbers, etc. The main point is to make the process simpler - so the users only need to input a few characters/choose a date/slide to the right number, instead of filling out this complicated configuration.

Some of such components are provided by kendo (e.g. DateRangePicker), others aren't (e.g. the above-mentioned slider; at least I didn't find anything like it), but could be implemented with a custom function. Either way, I can't seem to be able to override the default filter menu.

The only promising suggesstion on how to achieve something like this that I found was:

grid.Columns(c => c.Bound(item.Name)
       .Filterable(ftb => ftb.UI("datePickerFilter"))
function datePickerFilter(element) {
    element.kendoDateRangePicker({
        messages: {
            startLabel: "Check-In",
            endLabel: "Check-Out"
        },
        format: "MM/dd/yyyy"
    });
}
Unfortunately, it did not work. So any help, advice or personal experience with a similar issue will be very much appreciated :) Thanks.
Filter
Grid
Anton Mironov
Telerik team
 answered on 03 Apr 2025
0 answers
30 views
Gantt not showing timeline

Hi, I copied the gantt chart demo from the link below. I do not receive any errors but nothing shows in the timeline. Any idea what I am doing wrong? thank you 

 

ui-for-aspnet-core-examples/Telerik.Examples.RazorPages/Telerik.Examples.RazorPages/Pages/Gantt/GanttIndex.cshtml at master · telerik/ui-for-aspnet-core-examples · GitHub

Gantt
superBren
Top achievements
Rank 1
 asked on 02 Apr 2025
0 answers
60 views
Loader Components as a Loading/Processing Container

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)
    )
 
General Discussions
Loader
Andrew
Top achievements
Rank 1
Veteran
Iron
 updated question on 28 Mar 2025
1 answer
102 views
Telerik UI for ASP.NET Core 2025.1.227 Will Work under .Net 6.0 Application
We are currently using telerik.ui.for.aspnet.core.2020.1.406 where the application is using .Net 6.0, we are planning to upgrade to latest supported version of Telerik UI for ASP.NET Core for that application. Will latest Telerik UI for ASP.NET Core 2025.1.227 work with no isseus under .Net 6.0 Application
General Discussions
Eyup
Telerik team
 answered on 27 Mar 2025
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