Class ObserveQuery<TArg, TResult>

Namespace

Phetch.Blazor

Assembly

Phetch.Blazor.dll

Blazor component to subscribe to a query and re-render when it changes.

public sealed class ObserveQuery<TArg, TResult> : ComponentBase, IComponent, IHandleEvent, IHandleAfterRender, IDisposable

Type Parameters

TArg

TResult

Inheritance

object

ComponentBase

ObserveQuery<TArg, TResult>

Implements

IComponent

IHandleEvent

IHandleAfterRender

IDisposable

Inherited Members

ComponentBase.SetParametersAsync(ParameterView)

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

This be used standalone, to trigger re-renders and events:

<ObserveQuery Target="query" OnChanged="StateHasChanged" />

Or, it can be used as a wrapper around other components, to automatically re-render only the wrapped content:

<ObserveQuery Target="query">
    @* Put content that depends on the query here. *@
</ObserveQuery>

See https://jcparkyn.github.io/phetch/docs/using-query-objects-directly.html for more information.

Properties

ChildContent

[Parameter]
public RenderFragment? ChildContent { get; set; }

Property Value

RenderFragment

DetachWhenDisposed

Automatically detach this query when this component is disposed. Only use this when this is the only component using this query instance, and the ObserveQuery is not rendered conditionally. Otherwise, implement IDisposable and call Detach() to detach the query manually.

[Parameter]
public bool DetachWhenDisposed { get; set; }

Property Value

bool

OnChanged

Callback function to call whenever the query state changes. This is usually used to trigger component re-renders using StateHasChanged.

[Parameter]
public Action OnChanged { get; set; }

Property Value

Action

OnFailure

Callback function to call when the query fails. This will only be called if this component is still mounted when the query fails. If you make multiple requests at the same time, this will only be called for the last request.

[Parameter]
public Action<QueryFailureEventArgs<TArg>>? OnFailure { get; set; }

Property Value

Action<QueryFailureEventArgs<TArg>>

OnSuccess

Callback function to call when the query succeeds. This will only be called if this component is still mounted when the query succeeds. If you make multiple requests at the same time, this will only be called for the last request.

[Parameter]
public Action<QuerySuccessEventArgs<TArg, TResult>>? OnSuccess { get; set; }

Property Value

Action<QuerySuccessEventArgs<TArg, TResult>>

Target

[Parameter]
[EditorRequired]
public IQuery<TArg, TResult>? Target { get; set; }

Property Value

IQuery<TArg, TResult>

Methods

BuildRenderTree(RenderTreeBuilder)

Renders the component to the supplied RenderTreeBuilder.

protected override void BuildRenderTree(RenderTreeBuilder builder)

Parameters

builder RenderTreeBuilder

A RenderTreeBuilder that will receive the render output.

Dispose()

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

public void Dispose()