/// <summary>
/// <para>
/// Appends a frame representing an <see cref="EventCallback"/> attribute.
/// </para>
/// <para>
/// The attribute is associated with the most recently added element. If the value is <c>null</c> and the
/// current element is not a component, the frame will be omitted.
/// </para>
/// </summary>
/// <param name="sequence">An integer that represents the position of the instruction in the source code.</param>
/// <param name="name">The name of the attribute.</param>
/// <param name="value">The value of the attribute.</param>
/// <remarks>
/// This method is provided for infrastructure purposes, and is used to support generated code
/// that uses <see cref="EventCallbackFactory"/>.
/// </remarks>
public void AddAttribute <TArgument>(int sequence, string name, EventCallback <TArgument> value)
{
AssertCanAddAttribute();
if (_lastNonAttributeFrameType == RenderTreeFrameType.Component)
{
// Since this is a component, we need to preserve the type of the EventCallback, so we have
// to box.
_entries.AppendAttribute(sequence, name, value);
}
else if (value.RequiresExplicitReceiver)
{
// If we need to preserve the receiver - we convert this to an untyped EventCallback. We don't
// need to preserve the type of an EventCallback<T> when it's invoked from the DOM.
_entries.AppendAttribute(sequence, name, value.AsUntyped());
}
else if (value.HasDelegate)
{
// In the common case the receiver is also the delegate's target, so we
// just need to retain the delegate. This allows us to avoid an allocation.
_entries.AppendAttribute(sequence, name, value.Delegate);
}
else
{
// Track the attribute name if needed since we elided the frame.
TrackAttributeName(name);
}
}