Concurrency error when deleteing or updating multiple primary key fields


Replace the code in method returns null, the department was deleted by another user.In that case the code uses the posted form values to create a department entity so that the Edit page can be redisplayed with an error message. code-html] Run the app and go to the Departments Index page.When the Http Get method is called with an error flag set to true in order to redisplay the confirmation page with an error message.It's also possible that zero rows were affected because the row was deleted by another user, so in that case no error message is displayed. code-csharp] The method accepts an optional parameter that indicates whether the page is being redisplayed after a concurrency error.Some of the options include the following: exceptions that the Entity Framework throws.



Jane clicks Save first and sees her change when the browser returns to the Index page.Optimistic concurrency means allowing concurrency conflicts to happen, and then reacting appropriately if they do.For example, Jane visits the Department Edit page and changes the Budget amount for the English department from $350,000.00 to $0.00.(The CLR requires overloaded methods to have different method parameters.) Now that the signatures are unique, you can stick with the MVC convention and use the same name for the Http Post and Http Get delete methods.

If the department is already deleted, the method returns false and the application just goes back to the Index method.

Therefore, you must configure the database and the data model appropriately.


Concurrency error when deleteing or updating multiple primary key fields comments


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