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How to: Specify When Concurrency Exceptions are Thrown

In LINQ to SQL, a ChangeConflictException exception is thrown when objects do not update because of optimistic concurrency conflicts. For more information, see Optimistic Concurrency: Overview.

Before you submit your changes to the database, you can specify when concurrency exceptions should be thrown:

  • Throw the exception at the first failure (FailOnFirstConflict).

  • Finish all update tries, accumulate all failures, and report the accumulated failures in the exception (ContinueOnConflict).

When thrown, the ChangeConflictException exception provides access to a ChangeConflictCollection collection. This collection provides details for each conflict (mapped to a single failed update try), including access to the MemberConflicts collection. Each member conflict maps to a single member in the update that failed the concurrency check.

Example

The following code shows examples of both values.

Northwnd db = new Northwnd("...");

// Create, update, delete code.

db.SubmitChanges(ConflictMode.FailOnFirstConflict);
// or
db.SubmitChanges(ConflictMode.ContinueOnConflict);

See also