Destruction of vue component reuse

the project uses vue+iview for development, the current problems encountered:
each module includes the left menu bar, the right display area, a .vue file on the menu bar, and the right display area corresponds to a different .vue file.
when I jump from one module to another module, there is no problem in beforeDestory () to operate the sub-components I want to destroy.
but I"m inside the same module, and when I destroy components (these components share a menu on the left. Vue and subcomponents), the subcomponent I get in beforeDestory () is null. Why is this? during
, I also read a lot of materials and tried to use beforeRouteUpdate, but because beforeRouteUpdate can only be used in the .vue file of the left menu tree, there is no substantive operation on the destruction of subcomponents called in the .vue file in the right display area. Answer

Nov.10,2021

try the keeplive? in the route

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