Official explanation: Force vue instances to re-render. Note that it affects only the instance itself and the subcomponents that insert the contents of the slot, not all subcomponents.
equivalent to manually triggering render()
this.$forceUpdate();perform forced rendering. for example, there are too many data levels, and the render function is not automatically updated, so it needs to be manually forced to refresh.
calling the force update method updates the view and data, triggering the updated lifecycle.this.$forceUpdate()
Sometimes when using multi-level for loop nesting, the page does not refresh the changed value in time, you should use this.$forceUpdate()
