blocks|key|4656922|text|Entity+Framework不支持触发器，尽管您当然可以手动执行将创建触发器的语句，但您需要在创建表之后执行此操作(如果使用迁移)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4656923|您可以在EF+4.1+code-first+adding+a+trigger+to+a+table中使用Ladislav指定的技术|offset|length|4656924|注意他的警告，然而，EF将不会意识到触发器中所做的任何更改。如果您的意图仅仅是确保表中的两列不为空，那么最好使用约束(+EF也不支持约束，但您可以手动添加它们)。|4656925|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/5913581/1743997^0|0|4|19|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@$D|R|E|S|1|T]]|A|$]]|$1|F|3|G|5|6|7|U|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

Entity Framework has no support for triggers, although you can certainly manually execute a statement that would create a trigger, but you would need to do this after the table was created (if using migrations).

You can use the technique specified by Ladislav in <a href="https://stackoverflow.com/a/5913581/1743997">EF 4.1 code-first adding a trigger to a table</a>

Take note of his warning, however, EF will not be aware of any changes made in the trigger. If your intent is merely to ensure that 2 columns in a table are not null, you'd be better served with a constraint (constraints are also not supported by EF, but you can add them manually).

blocks|key|150661|text|查看我的库EntityFramework.Triggers。它在实体框架层工作，因此如果有人直接修改数据库，则不会触发触发器事件。NuGet链接为https://www.nuget.org/packages/EntityFramework.Triggers/|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|150662|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/NickStrupat/EntityFramework.Triggers|1|https://www.nuget.org/packages/EntityFramework.Triggers/^0|5|O|0|21|1K|1|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]|$A|R|B|S|1|T]]|C|$]]|$1|D|3|-4|5|6|7|U|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]|L|$5|G|H|I|C|$J|M]]]]

Check out my library <a href="https://github.com/NickStrupat/EntityFramework.Triggers" rel="noreferrer">EntityFramework.Triggers</a>. It works at the Entity Framework layer, so the trigger events won't fire if someone modifies the database directly. The NuGet link is <a href="https://www.nuget.org/packages/EntityFramework.Triggers/" rel="noreferrer">https://www.nuget.org/packages/EntityFramework.Triggers/</a>

blocks|key|4656986|text|尽管我的library只适用于最新版本的EfCore，但它可能会对某些人有用。它扩展了SQL语法，将其转换成ModelBuilder，并通过migrationBuilder.Sql()应用接收到的代码。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|4656987|modelBuilder.Entity<Transaction>()
++++.AfterUpdate(trigger+=>+trigger
++++++++.Action(action+=>+action
++++++++++++.Condition((transactionBeforeUpdate,+transactionAfterUpdate)+=>+transactionBeforeUpdate.IsVeryfied+&&+transactionAfterUpdate.IsVeryfied)+//+Executes+only+if+condition+met+
++++++++++++.Update<UserBalance>(
++++++++++++++++(transactionBeforeUpdate,+transactionAfterUpdate,+userBalances)+=>+userBalances.UserId+==+oldTransaction.UserId,+//+Will+be+updated+entities+with+matched+condition
++++++++++++++++(oldTransaction,+updatedTransaction,+oldBalance)+=>+new+UserBalance+{+Balance+=+oldBalance.Balance+%2B+updatedTransaction.Value+-+oldTransaction.Value+})));+//+New+values+for+matched+entities.|code-block|syntax|javascript|4656988|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/win7user10/Laraue.EfCoreTriggers^0|4|7|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Maybe my <a href="https://github.com/win7user10/Laraue.EfCoreTriggers" rel="nofollow noreferrer">library</a> will be useful for someone, though it works only with the latest version of EfCore. It extends ModelBuilder syntax, translates it into SQL, and applies received code via migrationBuilder.Sql().
<pre><code>modelBuilder.Entity&lt;Transaction&gt;()
 .AfterUpdate(trigger =&gt; trigger
 .Action(action =&gt; action
 .Condition((transactionBeforeUpdate, transactionAfterUpdate) =&gt; transactionBeforeUpdate.IsVeryfied &amp;&amp; transactionAfterUpdate.IsVeryfied) // Executes only if condition met 
 .Update&lt;UserBalance&gt;(
 (transactionBeforeUpdate, transactionAfterUpdate, userBalances) =&gt; userBalances.UserId == oldTransaction.UserId, // Will be updated entities with matched condition
 (oldTransaction, updatedTransaction, oldBalance) =&gt; new UserBalance { Balance = oldBalance.Balance + updatedTransaction.Value - oldTransaction.Value }))); // New values for matched entities.
</code></pre>

I'm using Entity Framework 6 Code First, and would like to create a Trigger.

How do I do this?

The reason I need the trigger is because a user may either edit the database directly or through a program I'm writing, and I need to make sure 2 columns in a table are not both null, and are not both not null.

I've been looking and can't find a way.

Is there any way to specify a trigger using code first?

Entity Framework 6 Code First Trigger

数据库

我首先使用Entity Framework6代码，并想创建一个触发器。我该怎么做呢？我需要触发器的原因是因为用户可以直接编辑数据库，也可以通过我编写的程序编辑数据库，并且我需要确保表中的两列不都是null，也不是都不是null。我一直在找，但是找不到办法。有没有办法先用代码来指定触发器？

问实体框架6代码优先触发器
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