Get all Identity roles in ASP .Net Core WebAPI - asp.net-web-api

Question

I have a task to fetch all identity roles in my database. i use below code to fetch all roles. in Asp .Net core WebAPI
UserRoleService.cs
public class UserRoleService
{
private readonly RoleManager<IdentityRole> _roleManager;
public UserRoleService(RoleManager<IdentityRole> roleManager)
{
_roleManager=roleManager;
}
public Task<IList<string>> AllUserRoles(){
return _roleManager.Roles;
}
}
But i got following Error
Cannot implicitly convert type
'System.Linq.IQueryable<Microsoft.AspNetCore.Identity.IdentityRole>' to
'System.Threading.Tasks.Task<System.Collections.Generic.List<string>>'.
An explicit conversion exists (are you missing a cast?)
plese give me a solution to solve this error
when i change it to
Task<List<IdentityRole>> AllUserRoles()
{
return _roleManager.Roles;
}
I got error like
Cannot implicitly convert type
'System.Linq.IQueryable<Microsoft.AspNetCore.Identity.IdentityRole>' to
'System.Threading.Tasks.Task<System.Collections.Generic.List<Microsoft.AspNetCore.Identity.IdentityRole>>'.
An explicit conversion exists (are you missing a cast?)

Answer 1

I think that the problem is the return type you are using there.
From your code, I assume that _roleManager.Roles is of type System.Linq.IQueryable<Microsoft.AspNetCore.Identity.IdentityRole>.
Your return type is instead Task<List<IdentityRole>> or Task<IList<string>>
You can change the return type of your function to IQueryable as this:
public List<IdentityRole> AllUserRoles()
{
return _roleManager.Roles.ToList();
}
or do something like:
public Task<List<IdentityRole>> AllUserRoles()
{
return Task.FromResult(_roleManager.Roles.ToList());
}