WPF FrameworkPropertyMetaData Journal——这有什么意义？

Question

基本上，正如标题所问:

Journal 属性有什么意义？ MSDN 并没有真正解释它的实际用途。

Answer 1

blog post 很好地解释了这一点，或上官方MSDN page .

总结一下:

Windows Presentation Foundation (WPF) supports browser-style navigation that can be used in two types of applications: standalone applications and XAML browser applications (XBAPs). To package content for navigation, WPF provides the Page class. You can navigate from one Page to another declaratively, by using a Hyperlink, or programmatically, by using the NavigationService. WPF uses the journal to remember pages that have been navigated from and to navigate back to them.
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If you need to remember small pieces of state across Page navigations, you can use dependency properties (see DependencyProperty) that are configured with the FrameworkPropertyMetadata.Journal metadata flag.