c# - 如何防止 EF Core 3.1 中的列更新？

Question

我从 .Net Core 2.2 升级到 3.1，但此功能已被弃用

modelBuilder
.Entity<Order>()
.Property(e => e.CreationTime)
.ValueGeneratedOnAddOrUpdate()
.Metadata.IsStoreGeneratedAlways = true;

我需要 EF 来执行插入但阻止更新。

谢谢!

Answer 1

据官方documentation , IsStoreGeneratedAlways 从 3.1 开始过时。

Microsoft.EntityFrameworkCore.Metadata Assembly:

If Throw, then an exception will be thrown if a new value is assigned to this property after the entity exists in the database.

If Ignore, then any modification to the property value of an entity that already exists in the database will be ignored.

你应该尝试这样的事情:

modelBuilder
    .Entity<Order>()
    .Property(e =>.CreationTime).Metadata.SetAfterSaveBehavior(PropertySaveBehavior.Ignore);