PropertyGrid 不支持 ExpandableObjectConverter

[w757703598]

Feature request type

sample request

Is your feature request related to a problem? Please describe

子类属性不能直接绑定，能否支持和winform一样的 TypeConverter 转换

Describe the solution you'd like

PropertyItem 增加Children属性。展开显示子项

Describe alternatives you've considered

No response

Additional context

No response