Question

For a given entity I can get all its references by calling

var references = dbContext.Entry(entity).References;

现在,我想把所有提法都提到无效。

foreach (var reference in references)
{
  reference.CurrentValue = null;
}
context.Update(entity);
context.SaveChanges();

但是,似乎仅仅提及无效是不够的,还必须确定外国关键财产。但是,如何找到外国关键领域来加以参考?

Answer 1

You can use Metadata property to get the associated INavigation, then ForeignKey property to get the associated IForeignKey, then the Properties property to get the associated properties of type IProperty, and finally the Name property which can be passed to Property method to obtain the associated PropertyEntry for manipulating the value.

采取行动:


var entry = dbContext.Entry(entity);
foreach (var reference in entry.References)
{
    reference.CurrentValue = null;
    foreach (var fkProperty in reference.Metadata.ForeignKey.Properties)
        entry.Property(fkProperty.Name).CurrentValue = null;
}

<>Update: 在最近的核心版本中,<代码>Metadata 房地产类型已改为INavigation 基地(可能作为准备航道性能支助的一部分)没有<编码>ForeignKey 财产,因此,需要人工将其投到上述<代码>INavigation接口,例如:

using Microsoft.EntityFrameworkCore.Metadata;
...
foreach (var fkProperty in ((INavigation)reference.Metadata).ForeignKey.Properties)
...

友情链接