下面的Entity Framework数据库优先方法面临问题。
我的模型班：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity.Spatial;
namespace LCM_API.Models
{
public partial class User
{
[Key]
public int UserId { get; set; }
[Required]
[StringLength(500)]
public string FirstName { get; set; }
[Required]
[StringLength(500)]
public string LastName { get; set; }
[Required(ErrorMessage = "Required EmailID")]
[RegularExpression(@"[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}", ErrorMessage = "Please enter Valid Email ID")]
[StringLength(500)]
public string Email { get; set; }
[StringLength(10)]
public string Phone { get; set; }
[Required]
[StringLength(10)]
public string AccessControl { get; set; }
[Required(ErrorMessage = "Required Username")]
[StringLength(10, MinimumLength = 2, ErrorMessage = "Username Must be Minimum 2 Charaters")]
public string UserName { get; set; }
[DataType(DataType.Password)]
[Required(ErrorMessage = "Required Password")]
[MaxLength(20, ErrorMessage = "Password cannot be Greater than 30 Charaters")]
[StringLength(21, MinimumLength = 7, ErrorMessage = "Password Must be Minimum 7 Charaters")]
public string Password { get; set; }
}
}
IRegisterUser界面
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using LCM_API.Models;
namespace LCM_API.Repositry
{
public interface IRegisterUser
{
User Add(User registeruser);
bool ValidateRegisteredUser(User registeruser);
bool ValidateUsername(User registeruser);
int GetLoggedUserID(User registeruser);
}
}
RegisterUser类
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using LCM_API.Models;
using System.Data.Entity;
namespace LCM_API.Repositry
{
public class RegisterUser:IRegisterUser
{
private LCMTestEntities _context ;
// Users usr = new Users();
public RegisterUser()
{
_context = new LCMTestEntities();
}
public User Add(User registeruser)
{
try
{
_context.RUser.Add(registeruser);
_context.SaveChanges();
return registeruser;
}
catch(Exception e)
{
throw e.InnerException;
}
}
public bool ValidateRegisteredUser(User registeruser)
{
var usercount = (from Users in _context.RUser
where Users.UserName == registeruser.UserName && Users.Password == registeruser.Password
select Users).Count();
if (usercount > 0)
{
return true;
}
else
{
return false;
}
}
public bool ValidateUsername(User registeruser)
{
var usercount = (from Users in _context.RUser
where Users.UserName == registeruser.UserName
select Users).Count();
if(usercount > 0)
{
return true;
}
else
{
return false;
}
}
public int GetLoggedUserID(User registeruser)
{
var usercount = (from Users
in _context.RUser
where Users.UserName == registeruser.UserName && Users.Password == registeruser.Password
select Users).Count();
return usercount;
}
}
}
UsersController类：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using a=System.Web.Http;
using b=System.Web.Mvc;
using System.Security.Cryptography;
using LCM_API.Models;
using LCM_API.Repositry;
using LCM_API.AES256Encryption;
namespace LCM_API.Controllers
{
public class UsersController : a.ApiController
{
IRegisterUser repository = new RegisterUser();
private LCMTestEntities ls = new LCMTestEntities();
// RegisterUser ru = new RegisterUser();
// public UsersController()
// {
// repositry = new RegisterUser();
// }
[a.Route("api/LCM/Create")]
[a.HttpPost]
public a.IHttpActionResult Create([a.FromBody]User usrs)
{
usrs.Password = EncryptionLibrary.EncryptText(usrs.Password);
User usr = repository.Add(usrs);
if (repository.ValidateUsername(usrs))
{
return Content(HttpStatusCode.Found, "User is already registered");
}
return Ok(usr);
}
[a.Route("api/LCM/GetUsers")]
public a.IHttpActionResult GetAllUsers()
{
var lm1= ls.RUser.SqlQuery("Select * from LCMTest.mag123.Users");
if (lm1 == null)
return NotFound();
return Ok(lm1);
}
}
}
我的DBContext班：
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Web;
namespace LCM_API.Models
{
using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
public partial class LCMTestEntities : DbContext
{
public LCMTestEntities()
: base("name=LCMTestEntities")
{
this.Configuration.LazyLoadingEnabled = true;
this.Configuration.ProxyCreationEnabled = true;
}
public virtual DbSet<AppData> LCMInfo { get; set; }
public virtual DbSet<User> RUser { get; set; }
public virtual DbSet<ClientKey> ClientKeys { get; set; }
public virtual DbSet<TokensManager> TokensManager { get; set; }
// protected override void OnModelCreating(DbModelBuilder modelBuilder)
// {
// }
}
}
当我尝试使用邮递员发布以下数据
{
"FirstName": "somename",
"LastName": "somename",
"Email": "xyzhab@gmail.com",
"Phone": "78654321",
"AccessControl": "Normal",
"UserName": "xyz123",
"Password": "hswuhwuddfrtx"
}
我在NullReferenceException上看到一个_context.SaveChanges()，上面写着
{
"$id": "1",
"Message": "An error has occurred.",
"ExceptionMessage": "Object reference not set to an instance of an object.",
"ExceptionType": "System.NullReferenceException",
"StackTrace": " at LCM_API.Repositry.RegisterUser.Add(User registeruser) in C:\\Program Files (x86)\\Microsoft Visual Studio\\Projects\\LCM_API\\LCM_API\\Repositry\\RegisterUser.cs:line 30\r\n at LCM_API.Controllers.UsersController.Create(User usrs) in C:\\Program Files (x86)\\Microsoft Visual Studio\\Projects\\LCM_API\\LCM_API\\Controllers\\UsersController.cs:line 31\r\n at lambda_method(Closure , Object , Object[] )\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass10.<GetExecutor>b__9(Object instance, Object[] methodParameters)\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.Execute(Object instance, Object[] arguments)\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Controllers.ApiControllerActionInvoker.<InvokeActionAsyncCore>d__0.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__2.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()"
}
这是格式化的堆栈跟踪：
at LCM_API.Repositry.RegisterUser.Add(User registeruser) in C:\\Program Files (x86)\\Microsoft Visual Studio\\Projects\\LCM_API\\LCM_API\\Repositry\\RegisterUser.cs:line 30
at LCM_API.Controllers.UsersController.Create(User usrs) in C:\\Program Files (x86)\\Microsoft Visual Studio\\Projects\\LCM_API\\LCM_API\\Controllers\\UsersController.cs:line 31
at lambda_method(Closure , Object , Object[] )
at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass10.<GetExecutor>b__9(Object instance, Object[] methodParameters)
at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.Execute(Object instance, Object[] arguments)
at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Web.Http.Controllers.ApiControllerActionInvoker.<InvokeActionAsyncCore>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()
过去1周来我一直在这个问题上停留，无法继续前进。请有人帮我解决这个问题。