我尝试用unitOFWOrk和genericRepository创建两个列表。我有一个对象Climb，它存在于一个文本字段（你可以填写攀登的名字）和两个列表：Country：你可以在哪里选择一个国家和一个列表：difficultGrade ，在那里你可以选择一个艰难的爬坡等级。
这是我创造攀登的方法：
public ActionResult Create()
{
var queryCountry = unitOfWork.ClimbRepository.Get(
orderBy: q => q.OrderBy(r => r.country.Climbs));
var queryDifficult = unitOfWork.ClimbRepository.Get(
orderBy: qd => qd.OrderBy(d => d.difficult.Climbs));
ViewBag.CountryId = new SelectList( queryCountry, "CountryId", "country_name");
ViewBag.DifficultId = new SelectList(queryDifficult, "DifficultId", "DifficultName");
return View();
}
这是Generic存储库：
public class GenericRepository<TEntity> where TEntity : class
{
internal LolaBikeContext context;
internal DbSet<TEntity> dbSet;
public GenericRepository(LolaBikeContext context)
{
this.context = context;
this.dbSet = context.Set<TEntity>();
}
public virtual IEnumerable<TEntity> GetWithRawSql(string query, params object[] parameters)
{
return dbSet.SqlQuery(query, parameters).ToList();
}
public virtual IEnumerable<TEntity> Get(
Expression<Func<TEntity, bool>> filter = null,
Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null,
string includeProperties = "")
{
IQueryable<TEntity> query = dbSet;
if (filter != null)
{
query = query.Where(filter);
}
foreach (var includeProperty in includeProperties.Split
(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries))
{
query = query.Include(includeProperty);
}
if (orderBy != null)
{
return orderBy(query).ToList();
}
else
{
return query.ToList();
}
}
public virtual TEntity GetByID(object id)
{
return dbSet.Find(id);
}
public virtual void Insert(TEntity entity)
{
dbSet.Add(entity);
}
public virtual void Delete(object id)
{
TEntity entityToDelete = dbSet.Find(id);
Delete(entityToDelete);
}
public virtual void Delete(TEntity entityToDelete)
{
if (context.Entry(entityToDelete).State == EntityState.Detached)
{
dbSet.Attach(entityToDelete);
}
dbSet.Remove(entityToDelete);
}
public virtual void Update(TEntity entityToUpdate)
{
dbSet.Attach(entityToUpdate);
context.Entry(entityToUpdate).State = EntityState.Modified;
}
}
UnitOFWork类：
public class UnitOfWork : IDisposable
{
private LolaBikeContext context = new LolaBikeContext ();
private GenericRepository<UserProfile> userRepository;
private GenericRepository<Route> routeRepository;
private GenericRepository<Climb> climbRepository;
private GenericRepository<Country> countryRepository;
public GenericRepository<UserProfile> UserRepository
{
get
{
if (this.userRepository == null)
{
this.userRepository = new GenericRepository<UserProfile>(context);
}
return userRepository;
}
}
public GenericRepository<Route> RouteRepository
{
get
{
if (this.routeRepository == null)
{
this.routeRepository = new GenericRepository<Route>(context);
}
return routeRepository;
}
}
public GenericRepository<Climb>ClimbRepository
{
get
{
if (this.climbRepository == null)
{
this.climbRepository = new GenericRepository<Climb>(context);
}
return this.climbRepository;
}
}
public void Save()
{
context.SaveChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
和我的viewModel：
public class ClimbViewModel
{
public ClimbViewModel()
{
Countries = new List<SelectListItem>();
}
public int Id { get; set; }
[Required(ErrorMessage="You need to give it a name")]
public string Name { get; set; }
public int SelectedValue { get; set; }
public int SelectedCountryId { get; set; }
public IEnumerable<SelectListItem> Countries { get; set; }
public IEnumerable<SelectListItem> DifficultGrades {get; set; }
}
问题当然是我如何获得国家名单和困难等级列表？
谢谢
在过去，我有这样的：
ViewBag.CountryId = new SelectList(db.countries, "CountryId", "country_name");
ViewBag.DifficultId = new SelectList(db.difficults, "DifficultId", "DifficultName");
但所以我用GenericRepository和UnitOfWork替换它们。但如果我这样做就像在这里做的那样。我收到此错误：
A first chance exception of type 'System.InvalidOperationException' occurred in EntityFramework.dll
Additional information: The entity type ClimbViewModel is not part of the model for the current context.
public ActionResult Create()
{
var queryCountry = unitOfWork.ClimbRepository.Get(
orderBy: q => q.OrderBy(r => r.country.Climbs));
var queryDifficult = unitOfWork.ClimbRepository.Get(
orderBy: qd => qd.OrderBy(d => d.difficult.Climbs));
ViewBag.CountryId = new SelectList( queryCountry, "CountryId", "country_name");
ViewBag.DifficultId = new SelectList(queryDifficult, "DifficultId", "DifficultName");
return View();
}
当然是错的。但我不知道如何改变这一点。我得到了这个错误：
An exception of type 'System.ArgumentException' occurred in EntityFramework.dll but was not handled in user code
Additional information: DbSortClause expressions must have a type that is order comparable.
这是堆栈跟踪：
at System.Data.Entity.Core.Common.CommandTrees.ExpressionBuilder.Internal.ArgumentValidation.ValidateSortClause(DbExpression key)
at System.Data.Entity.Core.Common.CommandTrees.ExpressionBuilder.DbExpressionBuilder.ToSortClause(DbExpression key)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OrderByTranslatorBase.TranslateOneLambda(ExpressionConverter parent, DbExpressionBinding sourceBinding, DbExpression lambda)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, DbExpression& source, DbExpressionBinding& sourceBinding, DbExpression& lambda)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.SequenceMethodTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, SequenceMethod sequenceMethod)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.TypedTranslate(ExpressionConverter parent, MethodCallExpression linq)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator`1.Translate(ExpressionConverter parent, Expression linq)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.Convert()
at System.Data.Entity.Core.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable`1 forMergeOption)
at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClass7.<GetResults>b__6()
at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClass7.<GetResults>b__5()
at System.Data.Entity.Infrastructure.DbExecutionStrategy.Execute[TResult](Func`1 operation)
at System.Data.Entity.Core.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
at System.Data.Entity.Core.Objects.ObjectQuery`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0()
at System.Data.Entity.Internal.LazyEnumerator`1.MoveNext()
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
at ContosoUniversity.DAL.GenericRepository`1.Get(Expression`1 filter, Func`2 orderBy, String includeProperties) in d:\Mijn Documents\My Web Sites\Lolabikes - Copy\C#\ContosoUniversity\DAL\GenericRepository.cs:line 46
at ContosoUniversity.Controllers.ClimbController.Create() in d:\Mijn Documents\My Web Sites\Lolabikes - Copy\C#\ContosoUniversity\Controllers\ClimbController.cs:line 68
at lambda_method(Closure , ControllerBase , Object[] )
at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.Async.AsyncControllerActionInvoker.ActionInvocation.InvokeSynchronousActionMethod()
at System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState)
at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
at System.Web.Mvc.Async.AsyncResultWrapper.End[TResult](IAsyncResult asyncResult, Object tag)
at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3d()
at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass46.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f()
好的，我现在就像这样：
public ActionResult Create()
{
var queryCountry = unitOfWork.CountryRepository.Get(orderBy: q => q.OrderBy(c =>c.country_name));
var queryDifficult = unitOfWork.DifficultRepository.Get(orderBy: q => q.OrderBy(d => d.DifficultName));
ViewBag.CountryId = new SelectList( queryCountry, "CountryId", "country_name");
ViewBag.DifficultId = new SelectList(queryDifficult, "DifficultId", "DifficultName");
return View();
}
所以我的UnitOfwork现在看起来像这样：
public class UnitOfWork : IDisposable
{
private LolaBikeContext context = new LolaBikeContext ();
private GenericRepository<UserProfile> userRepository;
private GenericRepository<Route> routeRepository;
private GenericRepository<Climb> climbRepository;
private GenericRepository<Country> countryRepository;
private GenericRepository<Difficult> difficultRepository;
private GenericRepository<ClimbViewModel> climbViewModelRepository;
public GenericRepository<UserProfile> UserRepository
{
get
{
if (this.userRepository == null)
{
this.userRepository = new GenericRepository<UserProfile>(context);
}
return userRepository;
}
}
public GenericRepository<Route> RouteRepository
{
get
{
if (this.routeRepository == null)
{
this.routeRepository = new GenericRepository<Route>(context);
}
return routeRepository;
}
}
public GenericRepository<Climb>ClimbRepository
{
get
{
if (this.climbRepository == null)
{
this.climbRepository = new GenericRepository<Climb>(context);
}
return this.climbRepository;
}
}
public GenericRepository<ClimbViewModel> ClimbViewModelRepository
{
get
{
if (climbViewModelRepository == null)
{
this.climbViewModelRepository = new GenericRepository<ClimbViewModel>(context);
}
return this.climbViewModelRepository;
}
}
public GenericRepository<Country>CountryRepository
{
get
{
if (this.countryRepository != null)
{
countryRepository = new GenericRepository<Country>(context);
}
return this.countryRepository;
}
}
public GenericRepository<Difficult>DifficultRepository
{
get
{
if (difficultRepository != null)
{
difficultRepository = new GenericRepository<Difficult>(context);
}
return this.difficultRepository;
}
}
public void Save()
{
context.SaveChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
但现在我收到这个错误：
A first chance exception of type 'System.NullReferenceException' occurred in ContosoUniversity.dll
Additional information: Object reference not set to an instance of an object.
我现在这样：
var queryCountry = unitOfWork.ClimbRepository.Get(
orderBy: q => q.OrderBy(r => r.country.country_name));
var queryDifficult = unitOfWork.ClimbRepository.Get(
orderBy: qd => qd.OrderBy(d => d.difficult.DifficultName));
但后来我得到了这个错误：
A first chance exception of type 'System.Web.HttpException' occurred in System.Web.dll
Additional information: DataBinding: 'System.Data.Entity.DynamicProxies.Climb_0568B2C1C64C1C347E3DF33E87F37C8D672D9794887F77C523EB7B16E9399FCE' does not contain a property with
在这条线上：
<div class="form-group">
<label class="control-label col-md-2" for="CountryID">Country</label>
@Html.DropDownList("CountryId", ViewBag.countries as SelectList, new { @class = "form-control", style = "width: 250px;" })
</div>
这是我的国家班：
public class Country
{
//[Key]
public int CountryId { get; set; }
public string country_code { get; set; }
[DisplayName("Country")]
public string country_name { get; set; }
public virtual ICollection<Climb> Climbs { get; set; }
public virtual ICollection<Route> Routes { get; set; }
}
和我的Climb课程：
public class Climb
{
[Key]
public int climbID { get; set; }
public string Name { get; set; }
public int Points { get; set; }
public int? UserProfileID { get; set; }
public int? CountryId { get; set; }
public int? DifficultId { get; set; }
public virtual UserProfile userProfile { get; set; }
public virtual Country country { get; set; }
public virtual Difficult difficult { get; set; }
}
这工作：
ViewBag.CountryId = new SelectList(db.countries, "CountryId", "country_name");
ViewBag.DifficultId = new SelectList(db.difficults, "DifficultId", "DifficultName");
但是如何用unitOfWork重写呢？
谢谢
您尝试添加的逻辑属于Model而不是Repository，存储库与它无关。负责的存储库是访问数据库并对其运行查询。
我写了一篇文章，介绍如何使用EF规划Thin存储库和工作单元
我将在https://www.codeproject.com/Articles/1157241/Very-Thin-Database-Layer-using-UnitOfWork-Pattern下面插入链接
希望这可以帮助