我有以下类(class):
class A
{
[PrimaryKey]
public int A_ID { get; set; }
[OneToMany(CascadeOperations=CascadeOperation.All)]
public List<B> Children { get; set; }
}
class B
{
[PrimaryKey]
public int B_ID { get; set; }
[ForeignKey(typeof(C))]
public int C_ID { get; set; }
}
class C
{
[PrimaryKey]
public int C_ID { get; set; }
}
当我有一个 A 的实例和 B 的子实例时,执行 db.InsertOrReplaceWithChildren(aInstance, recursive: true);
确实会导致 A 及其子 B 被插入到数据库中,但是每个外键值 B.C_ID
始终默认为 0,尽管它们有一个值。
例子:
A aInstance = new A();
aInstance.A_ID = 1;
B bInstance = new B();
bInstance.B_ID = 1;
C cInstance = new C();
cInstance.C_ID = 1;
bInstance.C_ID = cInstance.C_ID; //assigning the many-to-one foreign key of B to C
aInstance.Children.Add(bInstance); //assigning the one-to-many child record of A to B
//do the insert
db.InsertOrReplaceWithChildren(aInstance, recursive:true);
当我选择记录B时:
B bDatabaseRecord = db.Get<B>(bRecord => bRecord.B_ID == bInstance.B_ID).First();
//bDatabaseRecord.C_ID is 0 <-- the problem
最佳答案
我遇到了这个问题,它通过在类 B 中识别类 C 的对象(作为外键对象)并将关系标记为 ReadOnly=true 来解决。 所以代码应该是
class A
{
[PrimaryKey]
public int A_ID { get; set; }
[OneToMany(CascadeOperations=CascadeOperation.All)]
public List<B> Children { get; set; }
}
class B
{
[PrimaryKey]
public int B_ID { get; set; }
[OneToOne(ReadOnly=true)]
public C C_Obj { get; set; }
[ForeignKey(typeof(C))]
public int C_ID { get; set; }
}
class C
{
[PrimaryKey]
public int C_ID { get; set; }
}
我希望这个解决方案对你有用:)
关于c# - sqlite net extensions InsertOrReplaceWithChildren 不插入子外键字段,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/42234990/