Add custome vaildator

App/Services/Identity/Validators/AppRoleValidator.cs

@@ -0,0 +1,18 @@
+using System.Threading.Tasks;
+using App.Domain.Identity;
+using Microsoft.AspNetCore.Identity;
+
+namespace App.Services.Identity.Validators
+{
+    public class AppRoleValidator : RoleValidator<Role>
+    {
+        public AppRoleValidator(IdentityErrorDescriber errors) : base(errors)
+        {
+        }
+
+        public override Task<IdentityResult> ValidateAsync(RoleManager<Role> manager, Role role)
+        {
+            return base.ValidateAsync(manager, role);
+        }
+    }   
+}   

App/Services/Identity/Validators/AppUserValidator.cs

@@ -0,0 +1,37 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using App.Domain.Identity;
+using Microsoft.AspNetCore.Identity;
+
+namespace App.Services.Identity.Validators
+{
+    public class AppUserValidator : UserValidator<User>
+    {
+        public AppUserValidator(IdentityErrorDescriber errors) : base(errors)
+        {
+        }
+
+        public override async Task<IdentityResult> ValidateAsync(UserManager<User> manager, User user)
+        {
+            var result = await base.ValidateAsync(manager, user);
+
+            this.ValidateUserName(user,result.Errors.ToList());
+
+            return result;
+        }
+
+
+        private void ValidateUserName(User user, List<IdentityError> errors)
+        {
+            if (user.UserName.Contains("Admin"))
+            {
+                errors.Add(new IdentityError
+                {
+                    Code = "InvalidUser",
+                    Description = "این کاربر معتبر نیست"
+                });
+            }
+        }
+    }
+}

App/Startup.cs

@@ -57,6 +57,8 @@ public void ConfigureServices(IServiceCollection services)
                 })
                 .AddUserStore<AppUserStore>()
                 .AddRoleStore<AppRoleStore>()
+                .AddUserValidator<AppUserValidator>()
+                .AddRoleValidator<AppRoleValidator>()
                 .AddDefaultTokenProviders();
 
         }