庆军之blazor动态组件的研究与总结

只上代码:

rootcontrol.ControlParams = new Dictionary<string, object>();
rootcontrol.ControlParams["a"] = "ssss";
rootcontrol.Children.Add(new MControlParam()
{
ControlType = typeof(Layout),
ControlParams = new Dictionary<string, object>()
{
{ "Class", "page" },
{"ChildContent",new RenderFragment(childBuilder0 =>{
new MDynamicComponent(typeof(Button),new Dictionary<string, object>()
{
{ "OnClick",EventCallback.Factory.Create(this,this.fuckabc)},
{"ChildContent",new RenderFragment(childBuilder =>
{
timeTemplate(childBuilder);
childBuilder.AddContent(0, "第一个按钮");
})}
})._cachedRenderFragment(childBuilder0);

new MDynamicComponent(typeof(Button),new Dictionary<string, object>()
{
{"Block",false},
{"ChildContent",new RenderFragment(childBuilder =>
{
timeTemplate(childBuilder);
childBuilder.AddContent(0, "第二个按钮");
})}
})._cachedRenderFragment(childBuilder0);
})
}

} 
});

public class MDynamicComponent : IComponent
{
private RenderHandle _renderHandle;
public readonly RenderFragment _cachedRenderFragment;

/// <summary>
/// Constructs an instance of <see cref="DynamicComponent"/>.
/// </summary>
public MDynamicComponent()
{
_cachedRenderFragment = Render;
}

public MDynamicComponent(Type type, IDictionary<string, object> parameters)
: this()
{
Type = type;
Parameters = parameters;
}

/// <summary>
/// Gets or sets the type of the component to be rendered. The supplied type must
/// implement <see cref="IComponent"/>.
/// </summary>
[Parameter]
//[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
//[EditorRequired]
public Type Type { get; set; } = default!;

/// <summary>
/// Gets or sets a dictionary of parameters to be passed to the component.
/// </summary>
// Note that this deliberately does *not* use CaptureUnmatchedValues. Reasons:
// [1] The primary scenario for DynamicComponent is where the call site doesn't
// know which child component it's rendering, so it typically won't know what
// set of parameters to pass either, hence the developer most likely wants to
// pass a dictionary rather than having a fixed set of parameter names in markup.
// [2] If we did have CaptureUnmatchedValues here, then it would become a breaking
// change to ever add more parameters to DynamicComponent itself in the future,
// because they would shadow any coincidentally same-named ones on the target
// component. This could lead to application bugs.
[Parameter]
public IDictionary<string, object>? Parameters { get; set; }

/// <summary>
/// Gets rendered component instance.
/// </summary>
public object? Instance { get; private set; }

/// <inheritdoc />
public void Attach(RenderHandle renderHandle)
{
_renderHandle = renderHandle;
}

/// <inheritdoc />
//[UnconditionalSuppressMessage("Trimming", "IL2072", Justification = "We expect that types used with DynamicComponent will be defined in assemblies that don't get trimmed.")]
public Task SetParametersAsync(ParameterView parameters)
{
// This manual parameter assignment logic will be marginally faster than calling
// ComponentProperties.SetProperties.
foreach (var entry in parameters)
{
if (entry.Name.Equals(nameof(Type), StringComparison.OrdinalIgnoreCase))
{
Type = (Type)entry.Value;
}
else if (entry.Name.Equals(nameof(Parameters), StringComparison.OrdinalIgnoreCase))
{
Parameters = (IDictionary<string, object>)entry.Value;
}
else
{
throw new InvalidOperationException(
$"{nameof(MDynamicComponent)} does not accept a parameter with the name '{entry.Name}'. To pass parameters to the dynamically-rendered component, use the '{nameof(Parameters)}' parameter.");
}
}

if (Type is null)
{
throw new InvalidOperationException($"{nameof(MDynamicComponent)} requires a non-null value for the parameter {nameof(Type)}.");
}

_renderHandle.Render(_cachedRenderFragment);
return Task.CompletedTask;
}

void Render(RenderTreeBuilder builder)
{
builder.OpenComponent(0, Type);

if (Parameters != null)
{
foreach (var entry in Parameters)
{
builder.AddAttribute(1, entry.Key, entry.Value);
}
}

builder.AddComponentReferenceCapture(2, component => Instance = component);

builder.CloseComponent();
}
}

开始研究vue.js的render.