Blazor Window Overview

This article provides basic information about the Blazor Window component and its core features.

The Window component displays a popup window, which shows users custom content. The component provides predefined titlebar actions such as close, minimize and maximize. Custom actions are also supported. Other Window features include modality, resizing, and position control.

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Creating Blazor Window

  1. Use the TelerikWindow tag.
  2. Bind the Visible parameter to a bool property. It supports one-way and two-way binding.
  3. Add content to the WindowContent child tag.
  4. (optional) Add some title inside a WindowTitle tag. HTML markup and child components are supported, too.
  5. (optional) Add a Close action inside a <WindowActions> tag.
  6. (optional) Add a WindowFooter tag to include custom content in the bottom section of the Window.

Basic Blazor Window

<TelerikWindow @bind-Visible="@WindowIsVisible">
        Window Title
        Window Content ...
        <WindowAction Name="Close" />
        Window Footer Content ...

<TelerikButton OnClick="@( () => WindowIsVisible = !WindowIsVisible )">Toggle window</TelerikButton>

@code {
    bool WindowIsVisible { get; set; }


The Window can occupy a predefined size on the screen or expand automatically based on the content. By default, users can resize the Window. Read more about the Blazor Window size...


You can offset the position of the component with the Top and Left parameters. Read more about the Blazor Window position...


You can maximize, minimize, or close the Window through the action buttons in its titlebar. Read more about the Blazor Window action buttons...


You can move the Window on the page by dragging its titlebar. Read more about the Blazor Window dragging option...

The Window can be modal and prevent interacting with the rest of the page until it closes. Read more about the Blazor Window Modal...


The Window component fires events for visibility, state, size, and position changes. Use these events to respond to user actions. Read more about the Blazor Window Events...

Window Parameters

The following table lists the Window parameters, which are not discussed elsewhere in the component documentation. Also check the Window API for a full list of parameters and events.

Parameter Type and Default Value Description
Class string The custom CSS class of the <div class="k-window"> element. Use it to override theme styles. Here is a custom Window styling example.
PersistContent bool Determines if the Window content will be removed from the DOM (default) or hidden with CSS when the Window is minimized.
Size string A predefined Window width. Use the string members of the static class ThemeConstants.Window.Size - Small, Medium, and Large. They translate to widths of 300px, 800px and 1200px, respectively. If set, the Width parameter will take precedence over Size.
ThemeColor string A predefined color scheme for the Window, especially the titlebar. Use the available members of the static class ThemeConstants.Window.ThemeColor.
Visible bool Defines if the Window is rendered and visible on the page.
FooterLayoutAlign WindowFooterLayoutAlign enum
Controls the alignment of the HTML elements in the WindowFooter. Takes a member of the WindowFooterLayoutAlign enum. The possible options are Stretch, Start, End, and Center.

Window Reference and Methods

The Window methods are accessible through its reference.

Method Description
Refresh Redraws the component.

Get a reference to the Window and use its methods.

@* This code snippet showcases an example usage of the Refresh() method. *@

<TelerikButton OnClick="OpenWindow">Open Window</TelerikButton>

<TelerikWindow @ref="WindowRef" @bind-Visible="_windowVisible">
        Window Title
        <p role="status">Current count: @_currentCount</p>
        <TelerikButton OnClick="IncrementCount">Increment Count</TelerikButton>
        <TelerikButton OnClick="@(() => { _windowVisible = false; })">Close</TelerikButton>

@code {
    TelerikWindow WindowRef;

    private bool _windowVisible;

    private int _currentCount = 0;

    private void IncrementCount()


    private void OpenWindow()
        _windowVisible = true;


The Window component can adapt to different screen sizes by making it responsive to changes in the browser window. Here is an example that shows the two possible ways to achieve responsive Window behavior. The first method involves utilizing the Width and Height parameters of the component. The second method is to apply custom CSS styles.

Important Notes

The Telerik Window component renders as a child of the TelerikRootComponent at the root of the Blazor app. This is required, so it can show over the other page content, and have correct position.

In Blazor, however, the render tree structure may be important. In some cases, the special Window placement may put you in one of the following situations:

Next Steps

See Also

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