实体框架删除对象 - 并发错误（如何禁用并发）？
有没有办法禁用 EntityFramework 中抛出的并发错误？
例如：
using (xEntities5 entities = new xEntities5())
{
entities.Domains.MergeOption = System.Data.Objects.MergeOption.NoTracking;
Domain domain = new Domain() { DomainId = id };
EntityKey key = entities.CreateEntityKey(entities.CreateObjectSet<Domain>().EntitySet.Name, domain);
domain.EntityKey = key;
entities.Attach(domain);
//entities.AttachTo(entities.CreateObjectSet<Domain>().EntitySet.Name, domain);
entities.DeleteObject(domain);
return entities.SaveChanges(); // returns affected rows... must catch error?
}
有没有一种方法不必在 SaveChanges 周围进行 try/catch 来检测是否没有删除任何内容？
Is there a way to disable concurrency error thrown in EntityFramework?
For example:
using (xEntities5 entities = new xEntities5())
{
entities.Domains.MergeOption = System.Data.Objects.MergeOption.NoTracking;
Domain domain = new Domain() { DomainId = id };
EntityKey key = entities.CreateEntityKey(entities.CreateObjectSet<Domain>().EntitySet.Name, domain);
domain.EntityKey = key;
entities.Attach(domain);
//entities.AttachTo(entities.CreateObjectSet<Domain>().EntitySet.Name, domain);
entities.DeleteObject(domain);
return entities.SaveChanges(); // returns affected rows... must catch error?
}
Is there a way to not have to do try/catch around SaveChanges in order to detect if nothing was deleted?
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据我所知，您无法关闭并发错误。并发错误基于受影响的行数，因此如果您想要删除一行并且该行未被删除（例如因为它不再存在），则会引发并发异常。此外，
SaveChanges在事务中工作，因此如果您想删除 5 行，但只删除了 4 行，则会引发异常并回滚所有删除。如果您使用标记为
ConcurrencyMode.Fixed的列，并发测试可能会更加严格。这些列用于 SQL 语句的 where 条件，因此只能处理未修改的数据库记录。一旦出现并发异常，您就应该解决它。
As I know, you can't turn off concurrency error. Concurrency error is based on number of affected rows so if you want to delete a row and it is not deleted (for example because it doesn't exist any more) concurrency exception is fired. Moreover
SaveChangesworks in transaction so if you want to delete 5 rows and only 4 rows are deleted the exception is fired and all deletes are rolled back.Concurrency test can be even more restrictive if you use columns marked as
ConcurrencyMode.Fixed. These columns are used in where condition of SQL statements so only unmodified database records can be processed.Once you get concurrency exception you are supposed to solve it.
SaveChanges()会抛出异常，并且不会在内部捕获它们，所以如果想继续执行，就必须使用try/catch。 SaveChanges() 还返回一个方法，其中包含提交到数据库的实体数量，也就是说，如果没有发生错误:-)
HTH。
SaveChanges() will throw exceptions and doesn't catch them internally, so if you want to continue execution, you have to use try/catch. SaveChanges() also returns a method with the number of entities committed to the database, that is, if no error occurred :-)
HTH.