'宣言 Property Progress As C1.WPF.Document.AsyncActionProgressHandler(Of TProgress)
'使用法 Dim instance As IAsyncActionWithProgress(Of TProgress) Dim value As C1.WPF.Document.AsyncActionProgressHandler(Of TProgress) instance.Progress = value value = instance.Progress
C1.WPF.Document.AsyncActionProgressHandler<TProgress> Progress {get; set;}