Blazor route parameters 

when he remove id from url page display that there is no route by this url then , he add new route and this code id= id ?? "1" ;

That happened to me also. Apparently, if you have 2 routings in a component, OnInitializedAsync is called twice. Try with only one routing in the component and check again. It does not make any sense to me, but it behaves that way.

The same is true with employee public property! in fact, it seems like each time that you use inside (like, name) the debugger goes to EmployeeDetailComponentBase and reads the property like a round-trip. @kudvenkat

at _Host @(await Html.RenderComponentAsync(RenderMode.ServerPrerendered)) replace RenderMode.ServerPrerendered by RenderMode.Server

i have to initialize the Employee property like this public Employee Employee { get; set; } = new Employee(); this corrected my issue

@@zorigdavaag.8354 That's true it solves the problem but why is this? We didn't initilaize the Employees property in the EmployeeListBase class like here and still worked, so why is that?

Okay I guess it is because we check if it's null at EmployeeList component.

yes , you must forgot to take an object from Employees public Employees Employee{get; set;} = new Employees()

@Barri Duty you can Create relationship b/n the two entities then use Include(e => e.Departments); this way you have all the department information.....

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