EF5代碼第一個級聯刪除

Question

當我刪除一臺計算機時，有什麼辦法可以讓刪除級聯發生？基本上，當我刪除一臺計算機時，我希望它刪除實例及其所有參考，但環境和產品除外。

計算機實體：

public class Computer 
{ 
    [Key] 
    public int Id { get; set; } 

    public string IpAddress { get; set; } 

    public string Name { get; set; } 

    public string UserFriendlyName { get; set; } 

    public string Description { get; set; } 
} 

實例實體：

public class Instance 
{ 
    public Instance() 
    { 
     TestResults = new HashSet<TestResult>(); 
     Environments = new HashSet<Environment>(); 
    } 

    [Key] 
    public int Id { get; set; } 

    public string Name { get; set; } 

    public string Version { get; set; } 

    public string UserFriendlyName { get; set; } 

    public virtual Product Product { get; set; } 

    public virtual Profile LastKnownProfile { get; set; } 

    public virtual Computer Computer { get; set; } 

    public virtual ICollection<TestResult> TestResults { get; set; } 

    public virtual ICollection<Environment> Environments { get; set; } 
} 

Answer 1

您需要使用Fluent API定義關係。使用這樣的事情：

protected override void OnModelCreating(DbModelBuilder modelBuilder) 
{ 
    modelBuilder.Entity<Computer>() 
       .HasRequired(x => x.Instance) 
       .WithRequiredPrincipal(x => x.Computer) 
       .WillCascadeOnDelete(); 

    modelBuilder.Entity<Instance>() 
       .HasRequired(x => x.LastKnownProfile) 
       .WithRequiredPrincipal(x => x.Instance) 
       .WillCascadeOnDelete(); 

    modelBuilder.Entity<Instance>() 
       .HasMany(x => x.TestResults) 
       .WithOptional(x => x.Instance) 
       .WillCascadeOnDelete(); 
} 

這證明相當不錯的MSDN：Configuring Relationships with the Fluent API

Answer 2

檢查多對多relationship.is關閉級聯刪除國家和手動刪除相關記錄