c# – 实体框架自定义数据类型映射

概述鉴于此代码： public class Car { public virtual int CarId { get; set; } public virtual string TypeName { get; set; } public ConvertableNullable<double> Price { get; set; }} ConvertableNullable只 鉴于此代码：

public class Car {    public virtual int CarID { get; set; }    public virtual string Typename { get; set; }    public ConvertableNullable<double> Price { get; set; }}

ConvertableNullable只是Nullable的一种解决方法,但它并不是从它继承的.

现在,这是我的简单上下文,我将汽车类映射到实体,并映射它的每个属性

public class MyDBContext : DbContext {   public MyDBContext() : base(       "data source=.;initial catalog=newDB1;integrated security=True;" +         "multipleactiveresultsets=True;App=EntityFramework")   { }   protected overrIDe voID OnModelCreating(DbModelBuilder modelBuilder)   {       base.OnModelCreating(modelBuilder);       modelBuilder.Entity<Car>().HasKey(x=>x.CarID);       modelBuilder.Entity<Car>().Property(x => x.Typename);       modelBuilder.Entity<Car>().Property(x => x.Price);   }    public DbSet<Car> Cars { get; set; }}

现在当我尝试处理这个上下文时,它会引发异常

var db = new MyDBContext();// Throws exception "The property 'Price' is not a declared // property on type 'Car'. Verify that the property has not// been explicitly excluded from the model by using the Ignore// method or NotMappedAttribute data annotation. Make sure that// it is a valID primitive property."var c = db.Cars.ToList();

有什么建议？？

解决方法 唯一的解决方案是使用这样的东西：

public class Car {    public virtual int CarID { get; set; }    public virtual string Typename { get; set; }    // This must be accessible to the mapPing     public double? PriceData { get; set; }     public ConvertableNullable<double> Price     {         get { // Return data from PriceData }        set { // Set data to PriceData }    }}

您的映射将是：

modelBuilder.Entity<Car>().HasKey(x=>x.CarID);modelBuilder.Entity<Car>().Property(x => x.Typename);modelBuilder.Entity<Car>().Property(x => x.PriceData).HasColumnname("Price");modelBuilder.Entity<Car>().Ignore(x => x.Price);

问题是EF全局不支持@R_301_6942@标量类型.

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