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1 answer
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Hi all,

 

I've been observing a strange behavior and cannot seem to find out what causes it. This is primarily to collect some general ideas and learn about principles that I may have missed. I hate to say it but the fact I'm posting it here already suggests that Telerik Blazor UI might be involved, even if it is only by me using it wrong. Before I switched (from Bootstrap UI) to Telerik's Blazor UI, the solution operated more swiftly but was optically inconsistent if not outright ugly. Using Telerik Blazor UI introduced the desired consistency and working with the components is mostly a breeze. I don't regret my choice at all, and will do whatever is needed to keep it part of the solution.

For more context: this is about a multi-layered Blazor app (ASP.NET Core 8) using Telerik's Blazor UI to give users CRUD operations on medical case data. It is supposed to show data from an Oracle relational database with Entity Framework (EF Core 8). It's a data-first approach so I have built entity classes representing each table (about 30 tables in total now) and configured their relations mostly manually. But that's not actually the point. It's just to describe why I can't just paste a small code snippet here. It's a medical application so I'm legally unable to paste code 1:1 from my solution, and it's tons of code by now. Hope the description I'm giving below is enough to put you in the frame.

There are multiple Razor pages and components, some with more and some with less complexity:

  • entry pages where users select a quarter and doctor's office
  • next page reveals the cases that need work
  • selecting a case will go to the editor Blazor page which:
    • shows case basic data such as patient, insurance, summary
    • shows relational positional data in up to four separate grids (Telerik Data Grid) which are encapsulated in Razor components again to keep the main page as slim as possible
    • allows CUD operations and validations on relatonal data
    • uses models to do real-time calculations when users are modifying data
    • uses a persistence layer to collect changes and update storage

The editor page (the heaviest piece of the solution) features:

  • a Telerik menu bar
  • a Telerik breadcrumb bar
  • a Telerik dock manager
  • up to 8 dock panes, half containing Razor components rendering HTML tables, the other half being Telerik data grids
  • some interaction between DockManager and menu bar for menu items to control the visibility and arrangement of panes
  • lots of Telerik(MultiColumn)ComboBox, TelerikTextBox, TelerikDatePicker, TelerikNumericTextBox, TelerikMaskedTextBox etc. inside the panes for data representation and editing

All pages use InteractiveServer render mode as that is what I found works best for me. Until now, the software is only running on my dev machine in Visual Studio 2022, and most of the time in debug mode.

IMPORTANT: Let me emphasize that what I am describing here appears exclusively in debug mode as long as VS2022 is attached, and not when the solution is run by dotnet run. It's a p.i.t.a. though to debug with the handbrake engaged, and I'm not sure if the process does not hide a problem even when it runs without a debugger attached. It's just much faster then but that's not proof that whatever issue it is only affects the debug scenario.

The problems begin when I start navigating between the pages. Sometimes it's really fast, sometimes the same thing takes a lot of time. In my perception it might be related to how quickly I navigate but the actual trigger for the behavior is mostly unclear at this time. Heavier pages cause longer delays (and more exceptions along the way), while being loaded as well as while navigating away from them. But it's not consistent enough to point to an overall page or DOM size-related issue.

What struck me is that the debug console gets flooded with errors like these as delays are happening:

Exception thrown: 'Microsoft.JSInterop.JSDisconnectedException' in Microsoft.JSInterop.dll
Exception thrown: 'Microsoft.JSInterop.JSDisconnectedException' in System.Private.CoreLib.dll
Exception thrown: 'Microsoft.JSInterop.JSDisconnectedException' in System.Private.CoreLib.dll
Exception thrown: 'Microsoft.JSInterop.JSDisconnectedException' in Microsoft.AspNetCore.Components.Server.dll

The one from System.Private.CoreLib.dll appears twice most of the time, sometimes only once. A block like this is shown repeatedly up to 90 times in quick succession, in worse cases, sometimes only ten of these blocks appear in the console. But it's always this combination of the same three DLLs being addressed. When this happens, no other exceptions mix in, it's a constant stream of these three / four exceptions. The application is massively slowed down as this happens. Not as much as showing me a waiting indicator and reconnecting in the page though.

What's also interesting is that the user-end of the solution, besides being very slow at times, behaves fully normally. There are no errors or exceptions apparent to the user. To me this looks like the exceptions are silently consumed somewhere without giving further detail. Each occurrence takes some processing time. I can't say where the exceptions are thrown - probably somewhere deep inside the JS layers - but it's really unsettling and I have some doubts about moving this to production unless this is clarified a bit better.

The Edge browser's developer tools show nothing unusual. The JavaScript console there stays error-free, and running a network recording during a page refresh does show that loading takes very long (about 5 out of 10 seconds are spent with no traffic at all), but all HTTP operations have status 101 (switching protocols) or 200 (success). No error indication at all there.

I beg your pardon for being too unspecific where it may count but this is honestly my first Blazor application at all, and it's a monster of a project right away. I'm overwhelmed by the time pressure already and there's no team mates to help out. Random delays are the last thing I need.

So to wrap this up, what I'm looking for is basically guidance like:

  • is ServerInteractive (and no prerendering) a preferable mode to use globally?
  • do I have to clean up anything? I was hoping the Telerik components would take care of their memory allocations and connections on their own. If that's wrong or not enough, is IDisposable the way to go? What would have to be forcefully disposed?
  • are there any typical no-nos about Blazor apps that I might have missed, such as exceeding a hidden limit regarding the amount of HTML elements in the DOM, or having to keep the number of data grids to a minimum? Could two-way bindings be a root cause? (I'm using them a lot)
  • I'm using async wherever it makes sense, assuming that's the way to go nowadays. Anthing special about Blazor regarding async?
  • sometimes, I need to call StateHasChanged() to ensure the UI is up-to-date. This may indicate I'm missing a cleaner way to achieve the same, however, I couldn't find anything about this yet

Thank you all for reading, and in advance for any clues.

Cheers, have a nice day!

Joe

2 answers
41 views

Can you tell me how to get a consistent height for my huge "Create New" button?  I expected it to just use the space it needed instead of being 5X the size it is.

.gsi-height-32px{
    height: 32px !important;
}
<TelerikStackLayout Height="100%"
                    Width="100%"
                    Orientation="StackLayoutOrientation.Vertical">

    <TelerikButton OnClick="@OnCreate"
                   Class="gsi-width-100pct gsi-height-32px">
        Create New
    </TelerikButton>

    <TelerikGrid Data=@Patients
                 SelectedItems="SelectedPatients"
                 Pageable=true
                 PageSize="20"
                 Height="100%"
                 SelectionMode=GridSelectionMode.Single
                 SelectedItemsChanged="@((IEnumerable<Gsi.Customer.Models.Person> m) => OnPatientSelected(m))">

        <GridColumns>
            <GridColumn Field=@nameof(Person.FirstName) Title="First Name" />
            <GridColumn Field=@nameof(Person.LastName) Title="Last Name" />
            <GridColumn Field=@($"{nameof(Patient)}.{nameof(Patient.DateOfBirthDisplay)}") Title="Date of Birth" Width="125px" />
            <GridColumn Field=@($"{nameof(Patient)}.{nameof(Patient.GenderDisplay)}") Title="Sex" Width="100px" />
            <GridColumn Field=@nameof(Person.LastSessionTimestampDisplay) Title="Last Session" />
        </GridColumns>
    </TelerikGrid>
</TelerikStackLayout>

Joel
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Iron
Iron
 answered on 27 Jun 2025
1 answer
235 views
How do I tell the button to fill the available width?  I'd like this to be as wide as the other controls and it should adapt to width changes of the page.  I have this definition:

As a bonus, the only way I can get the button to align to the bottom is to put in the white label.  My attempts at aligning to the bottom have failed.


                        <TelerikCard Width="25vh">
                            <CardBody>

                                <div class="form-group-short">
                                    <label class="col-form-label">Patient Status</label><br />
                                    <TelerikDropDownList @bind-Value="@IsActiveFilterIndex"
                                                         TextField="Name" ValueField="Id"
                                                         ReadOnly="@(!IsActiveFilterEnabled)"
                                                         Data="@IsActiveFilterOptions">
                                    </TelerikDropDownList>
                                </div>
                                <div class="form-group-short align-bottom">
                                    <label class="col-form-label gsi-color-white">Apply Filter</label><br />
                                    <TelerikButton OnClick="OnFilter" Class="gsi-background-color gsi-color-white">
                                        Apply Filter
                                    </TelerikButton>
                                </div>
                            </CardBody>
                        </TelerikCard>

Justin
Telerik team
 answered on 23 May 2025
1 answer
54 views

Hello,

how can I make the clear-value button in the GridSearchBox always visible?
By default, the clear button only appears when the GridSearchBox has a value. I’d like it to always be visible, even when the input is empty.

Thanks

Anislav
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Bronze
 answered on 17 Apr 2025
1 answer
40 views

Do we have the ability to differentiate which button is clicked on the Edit Recurring Appointment window?

I'm using a custom edit form, but I don't know if there is a way to tell which button is selected on this window. The default form can differentiate the button chosen but I do not find anything in the args that tells me the selection.

Any help would be appreciated.

 

Hristian Stefanov
Telerik team
 answered on 21 Jan 2025
1 answer
103 views

Multiple clicking on button causing method(SaveAndSubmitClicked) to call twice. Even keeping bool variable(IsClicked ) to disable button not working.

OnClick="() => {IsClicked = true;SaveAndSubmitClicked();

Hristian Stefanov
Telerik team
 answered on 02 Dec 2024
1 answer
51 views

Is there a way to set the value attribute for a submit button when using the TelerikButton.

For example, this is the button markup I am currently using:


<button type="submit" class="login100-form-btn" name="provider" value="@provider.Name"
									title="Log in using your @provider.DisplayName account">
								<TelerikSvgIcon Icon="@GetExternalIcon(provider.Name)" Size="@ThemeConstants.SvgIcon.Size.ExtraExtraLarge" Class="me-3" />
								Login using @provider.DisplayName
							</button>
I want to convert this to using a TelerikButton but I cannnot figure out how to set the value attribute when doing that.
Nansi
Telerik team
 answered on 13 Nov 2024
1 answer
85 views
Hi All,

I have a TelerikButton within a PanelBarBinding element in an TelerikPanelBar, and i like to avoid the Panel to expand when i click the TelerikButton. However the Panel should expand if i click the Panel anywhere else.

how can i do this ? i use Telerik UI for Blazor ?


Thx

Hristian Stefanov
Telerik team
 answered on 30 Oct 2024
0 answers
246 views

We recently updated to Telerik.UI.for.Blazor 6.0.0 and now none of the forms on our website will submit using the "Enter" key on the keyboard. You must now either click or tab to the button and then hit enter.

This was not an issue with the previous version that we had pulled in.

Is there a fix for this or a new implementation pattern that needs to be used to support this?

billy
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Iron
Iron
Iron
 asked on 22 Aug 2024
0 answers
450 views

Hi,

We have an issue on our site that when you press an enter key on a second custom grid row (not a Telerik Grid, but rather a foreach that makes a new additive row) it will expand the first row when we press enter on any other row.

 

We've boiled it down to it possibly being a Telerik A11Y issue.

Is there a way we can stop a the button from reacting to an enter key press?

 

Kind regards,

Benjamin,

Benjamin
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 asked on 14 Jun 2024
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