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Question

我有一個與Service模型具有一對一關係的事務模型，然後服務模型有許多ServiceAddons。

public class Transaction 
{ 
    public int TransactionId {get;set;} 
    public string Username {get;set;} 
    public Service OccasionService {get;set;} 
} 

public class Service 
{ 
    [Key] 
    public int TransactionId {get;set;} 
    public Transaction Transaction { get; set; } 
    public virtual IList<ServiceAddon> ServiceAddons { get; set; } 
} 

public class ServiceAddon 
{ 
    public int ServiceAddonId { get; set; } 
    public int TransactionId { get; set; } 
    public int AddonId { get; set; } 
    public decimal AddonPrice { get; set; } 
    public virtual Addon Addon { get; set; } 
} 

現在軟件包管理器控制檯告訴我，OccasionServiceId不存在ServiceAddon，所以我改變了TRANSACTIONID它，編譯的程序，但現在它說無效的列OccasionServiceId。我該如何解決？

Answer 1

您需要指定ForeignKey s，請嘗試類似這樣的操作。我已經添加了對不清楚的位的評論。

public class Transaction 
{ 
    [Key] 
    public int TransactionId {get;set;} 
    public string Username {get;set;} 

    // Whatever the column is 
    public int OccasionServiceId {get;set;} 

    [ForeignKey("OccasionServiceId")] // What on Transaction points to Service's Key 
    public Service OccasionService {get;set;} 
} 

public class Service 
{ 
    // Ideally this would be called ServiceId instead? 
    [Key] 
    public int TransactionId {get;set;} 

    // If this uses TransactionId then are you sure you don't need a Key that is ServiceId 
    public Transaction Transaction { get; set; } 

    [ForeignKey("TransactionId")] // What on ServiceAddon points at Service's Key 
    public virtual ICollection<ServiceAddon> ServiceAddons { get; set; } 
} 

public class ServiceAddon 
{ 
    [Key] 
    public int ServiceAddonId { get; set; } 

    // Don't you need a ServiceId here? 

    public int TransactionId { get; set; } 
    public int AddonId { get; set; } 
    public decimal AddonPrice { get; set; } 
    public virtual Addon Addon { get; set; } 
} 

這裏是我的模型是什麼樣子，如果我做到了：

public class Transaction 
{ 
    [Key] 
    public int TransactionId {get;set;} 
    public string Username {get;set;} 
    public int ServiceId {get;set;} 

    [ForeignKey("ServiceId")] 
    public Service Service {get;set;} 
} 

public class Service 
{ 
    [Key] 
    public int ServiceId {get;set;} 
    public int TransactionId {get;set;} 

    [ForeignKey("TransactionId") 
    public Transaction Transaction { get; set; } 

    [ForeignKey("TransactionId")] // What on ServiceAddon points at Service's Key 
    public virtual ICollection<ServiceAddon> ServiceAddons { get; set; } 
} 

public class ServiceAddon 
{ 
    [Key] 
    public int ServiceAddonId { get; set; } 
    public int ServiceId {get;set;} 

    [ForeignKey("ServiceId")] 
    public Service Service {get;set;} 
}