Class NuvCaptcha

Namespace

NuvTools.Security.AspNetCore.Blazor.Captcha

Assembly

NuvTools.Security.AspNetCore.Blazor.dll

Reusable adaptive CAPTCHA (Google reCAPTCHA Enterprise) for public screens.

public class NuvCaptcha : ComponentBase, IComponent, IHandleEvent, IHandleAfterRender, IAsyncDisposable

Inheritance

object

ComponentBase

NuvCaptcha

Implements

IComponent

IHandleEvent

IHandleAfterRender

IAsyncDisposable

Inherited Members

ComponentBase.OnInitialized()

ComponentBase.OnInitializedAsync()

ComponentBase.OnParametersSet()

ComponentBase.OnParametersSetAsync()

ComponentBase.StateHasChanged()

ComponentBase.ShouldRender()

ComponentBase.OnAfterRender(bool)

ComponentBase.InvokeAsync(Action)

ComponentBase.InvokeAsync(Func<Task>)

ComponentBase.DispatchExceptionAsync(Exception)

ComponentBase.SetParametersAsync(ParameterView)

ComponentBase.RendererInfo

ComponentBase.Assets

ComponentBase.AssignedRenderMode

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

Runs invisible by default (score key, via execute) — nothing appears on screen. When the server flags the risk as high, the form calls RequireStepUpAsync() and the component renders the checkbox challenge (checkbox key) as a step-up. Driven by CaptchaOptions, registered with AddCaptcha.

Properties

Class

CSS class applied to the element that hosts the checkbox widget.

[Parameter]
public string? Class { get; set; }

Property Value

string

IsStepUp

Whether the component is already in checkbox (step-up) mode.

public bool IsStepUp { get; }

Property Value

bool

Methods

BuildRenderTree(RenderTreeBuilder)

Renders the component to the supplied RenderTreeBuilder.

protected override void BuildRenderTree(RenderTreeBuilder __builder)

Parameters

__builder RenderTreeBuilder

DisposeAsync()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources asynchronously.

public ValueTask DisposeAsync()

Returns

ValueTask

A task that represents the asynchronous dispose operation.

GetTokenAsync()

Gets the current token and mode. Without step-up: the invisible score token. In step-up: the checkbox token. When disabled, returns a non-empty token, since the server also skips verification in that mode.

public Task<(string? Token, string Mode)> GetTokenAsync()

Returns

Task<(string Token, string Mode)>

The token and the mode to send in the request headers.

HandleStepUpAsync(IResult)

Enters checkbox mode and returns true when the result carries the step-up marker (low score), meaning the caller should stop and let the user solve the challenge.

public Task<bool> HandleStepUpAsync(IResult result)

Parameters

result IResult

The result returned by the server call.

Returns

Task<bool>

true when the caller must wait for the user to solve the challenge.

OnAfterRenderAsync(bool)

Method invoked after each time the component has been rendered interactively and the UI has finished updating (for example, after elements have been added to the browser DOM). Any ElementReference fields will be populated by the time this runs.

This method is not invoked during prerendering or server-side rendering, because those processes are not attached to any live browser DOM and are already complete before the DOM is updated.

Note that the component does not automatically re-render after the completion of any returned Task, because that would cause an infinite render loop.

protected override Task OnAfterRenderAsync(bool firstRender)

Parameters

firstRender bool

Set to true if this is the first time OnAfterRender(bool) has been invoked on this component instance; otherwise false.

Returns

Task

A Task representing any asynchronous operation.

Remarks

The OnAfterRender(bool) and OnAfterRenderAsync(bool) lifecycle methods are useful for performing interop, or interacting with values received from @ref. Use the firstRender parameter to ensure that initialization work is only performed once.

RequireStepUpAsync()

Enters step-up: renders the checkbox for the user to confirm they are human.

public Task RequireStepUpAsync()

Returns

Task

ResetAsync()

Clears the checkbox challenge for a new attempt — the token is single-use.

public Task ResetAsync()

Returns

Task