aspnetcore/src/Microsoft.AspNetCore.Blazor.../Rendering/BrowserRendererEventDispatc...

101 lines
4.1 KiB
C#

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
using Microsoft.JSInterop;
using System;
namespace Microsoft.AspNetCore.Blazor.Browser.Rendering
{
/// <summary>
/// Provides mechanisms for dispatching events to components in a <see cref="BrowserRenderer"/>.
/// This is marked 'internal' because it only gets invoked from JS code.
/// </summary>
public static class BrowserRendererEventDispatcher
{
// TODO: Fix this for multi-user scenarios. Currently it doesn't stop people from
// triggering events for other people by passing an arbitrary browserRendererId.
//
// Preferred fix: Instead of storing the Renderer instances in a static dictionary
// store them within the context of a Circuit. Then we'll only look up the ones
// associated with the caller's circuit. This takes care of ensuring they are
// released when the circuit is closed too.
//
// More generally, we must move away from using statics for any per-user state
// now that we have multi-user scenarios.
/// <summary>
/// For framework use only.
/// </summary>
[JSInvokable(nameof(DispatchEvent))]
public static void DispatchEvent(
BrowserEventDescriptor eventDescriptor, string eventArgsJson)
{
var eventArgs = ParseEventArgsJson(eventDescriptor.EventArgsType, eventArgsJson);
var browserRenderer = BrowserRendererRegistry.CurrentUserInstance.Find(eventDescriptor.BrowserRendererId);
browserRenderer.DispatchBrowserEvent(
eventDescriptor.ComponentId,
eventDescriptor.EventHandlerId,
eventArgs);
}
private static UIEventArgs ParseEventArgsJson(string eventArgsType, string eventArgsJson)
{
switch (eventArgsType)
{
case "change":
return Json.Deserialize<UIChangeEventArgs>(eventArgsJson);
case "clipboard":
return Json.Deserialize<UIClipboardEventArgs>(eventArgsJson);
case "drag":
return Json.Deserialize<UIDragEventArgs>(eventArgsJson);
case "error":
return Json.Deserialize<UIErrorEventArgs>(eventArgsJson);
case "focus":
return Json.Deserialize<UIFocusEventArgs>(eventArgsJson);
case "keyboard":
return Json.Deserialize<UIKeyboardEventArgs>(eventArgsJson);
case "mouse":
return Json.Deserialize<UIMouseEventArgs>(eventArgsJson);
case "pointer":
return Json.Deserialize<UIPointerEventArgs>(eventArgsJson);
case "progress":
return Json.Deserialize<UIProgressEventArgs>(eventArgsJson);
case "touch":
return Json.Deserialize<UITouchEventArgs>(eventArgsJson);
case "unknown":
return Json.Deserialize<UIEventArgs>(eventArgsJson);
case "wheel":
return Json.Deserialize<UIWheelEventArgs>(eventArgsJson);
default:
throw new ArgumentException($"Unsupported value '{eventArgsType}'.", nameof(eventArgsType));
}
}
/// <summary>
/// For framework use only.
/// </summary>
public class BrowserEventDescriptor
{
/// <summary>
/// For framework use only.
/// </summary>
public int BrowserRendererId { get; set; }
/// <summary>
/// For framework use only.
/// </summary>
public int ComponentId { get; set; }
/// <summary>
/// For framework use only.
/// </summary>
public int EventHandlerId { get; set; }
/// <summary>
/// For framework use only.
/// </summary>
public string EventArgsType { get; set; }
}
}
}