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[英]Cannot insert explicit value for identity column when IDENTITY_INSERT is set to OFF. (Entity Framework Core)
[英]Entity Framework Core 6 - Cannot insert explicit value for identity column in table 'Roles' when IDENTITY_INSERT is set to OFF
我目前在使用 EF6 和 Fluent API 時遇到問題。 當插入模型具有一對多關系的數據庫時,出現此錯誤。 我檢查了一些相關主題,但我想保持自動增量。 沒有一對多關系的模型可以完美運行。
Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while saving the entity changes. See the inner exception for details.
---> Microsoft.Data.SqlClient.SqlException (0x80131904): Cannot insert explicit value for identity column in table 'Roles' when IDENTITY_INSERT is set to OFF.
at Microsoft.Data.SqlClient.SqlCommand.<>c.<ExecuteDbDataReaderAsync>b__188_0(Task`1 result)
at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
at System.Threading.Tasks.Task.<>c.<.cctor>b__272_0(Object obj)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)
--- End of stack trace from previous location ---
at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReaderAsync(RelationalCommandParameterObject parameterObject, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReaderAsync(RelationalCommandParameterObject parameterObject, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
ClientConnectionId:501a6880-e298-43d5-be69-fcbebacdb15e
Error Number:544,State:1,Class:16
--- End of inner exception stack trace ---
at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(IList`1 entriesToSave, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(StateManager stateManager, Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func`4 operation, Func`4 verifySucceeded, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
at WorkIT_Backend.Services.UserService.Create(String username, String password, String role) in C:\Users\Ondřej\Desktop\škola\2022 PRF\WS\OPR3\WorkIT_Backend\WorkIT_Backend\WorkIT_Backend\Services\UserService.cs:line 54
at WorkIT_Backend.Controllers.UsersController.CreateUser(UserDto user) in C:\Users\Ondřej\Desktop\škola\2022 PRF\WS\OPR3\WorkIT_Backend\WorkIT_Backend\WorkIT_Backend\Controllers\UsersController.cs:line 57
at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.TaskOfIActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeInnerFilterAsync>g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
at Swashbuckle.AspNetCore.SwaggerUI.SwaggerUIMiddleware.Invoke(HttpContext httpContext)
at Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider)
at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)
模型類
public sealed class Role
{
public long RoleId { get; set; }
public string? Name { get; set; }
public ICollection<User> Users { get; set; }
public Role()
{
Users = new HashSet<User>();
}
}
public class User
{
public long UserId { get; set; }
public string? UserName { get; set; }
public string? PasswordHash { get; set; }
public long RoleId { get; set; }
public virtual Role Role { get; set; }
public User()
{
}
}
數據庫上下文中的 OnModelCreating
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Role>(entity =>
{
entity.HasKey(q => q.RoleId);
entity.Property(q => q.RoleId)
.ValueGeneratedOnAdd();
entity.Property(q => q.Name)
.IsRequired();
entity.HasIndex(q => q.Name)
.IsUnique();
});
modelBuilder.Entity<User>(entity =>
{
entity.HasKey(q => q.UserId);
entity.Property(q => q.UserId)
.ValueGeneratedOnAdd();
entity.Property(q => q.UserName)
.IsRequired();
entity.Property(q => q.PasswordHash)
.IsRequired();
entity.HasOne(u => u.Role)
.WithMany(r => r.Users)
.HasForeignKey(u => u.RoleId)
.OnDelete(DeleteBehavior.ClientSetNull);
});
}
服務中添加用戶的方法
public async Task<User> Create(string username, string password, string role)
{
EnsureNotNull(username, nameof(username));
EnsureNotNull(password, nameof(password));
EnsureNotNull(role, nameof(role));
username = username.ToLower();
if (_context.Users.Any(q => q.UserName == username))
throw CreateException($"User {username} already exists.", null);
var hash = _securityService.HashPassword(password);
var userRole = await _roleService.GetRole(role);
var ret = new User {UserName = username, PasswordHash = hash, Role = userRole};
_context.Users.Add(ret);
await _context.SaveChangesAsync();
return ret;
}
這種添加角色的方法非常有效
public class RoleService
{
private readonly WorkItDbContext _context;
private readonly SecurityService _securityService;
public RoleService(WorkItDbContext context, SecurityService securityService)
{
_context = context;
_securityService = securityService;
}
public async Task<Role> Create(string name)
{
EnsureNotNull(name, nameof(name));
name = name.ToLower();
if (_context.Roles.Any(q => q.Name == name))
throw CreateException($"Role {name} already exists.", null);
var ret = new Role {Name = name};
_context.Add(ret);
await _context.SaveChangesAsync();
return ret;
}
public async Task<List<Role>> GetRoles()
{
var roles = await _context.Roles.ToListAsync();
return roles;
}
public async Task<Role> GetRole(string name)
{
var role = await _context.Roles.FirstAsync(q => q.Name == name) ??
throw CreateException($"Role {name} does not exist.");
return role;
}
}
程序.cs
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddSingleton<IConfiguration>(builder.Configuration);
SecurityService securityService = new(builder.Configuration);
builder.Services.AddTransient<WorkItDbContext>();
builder.Services.AddSingleton<SecurityService>();
builder.Services.AddTransient<UserService>();
builder.Services.AddTransient<RoleService>();
我有不同的 dbcontext 方法組合。 我嘗試通過注釋自動遞增 - 身份。 我已經檢查過 SQL Server 並且自動增量沒問題。
改變
builder.Services.AddTransient<WorkItDbContext>();
到
builder.Services.AddDbContext<WorkItDbContext>();
然后您的 UserService 和 RoleService 將共享一個 WorkItDbContext,因為它將作為 Scoped 服務添加。 請參閱ASP.NET Core 的依賴注入中的 DbContext
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