ado.net实体的准系统浅序列化

Question

I realize there are loads of questions already posted regarding serialization of ADO.Net entities, but I haven't had any luck finding one that really addresses quite what I want to do.

Basically, I need a really bare-bones, shallow JSON or plain-object representation of an ADO.Net entity. The purpose is for change-logging; ie when a record is going to be changed, I want to snag a copy of its data "before" and "after", and log the change.

I don't want any of the navigation, complex or other properties to be considered; just the scalar properties of the entity. If I miss some data that only would appear in special cases, that's fine -- just trying to do a rough log. Ideally my final code should look something like this:

Employee emp = db.Employees.First();

string oldRecordJSON = MySerializer.serialize(emp);

emp.Name = "Fred";
db.saveChanges();

string newRecordJSON = MySerializer.serialize(emp);

ChangeLog.logDBChange("Employees", emp.ID, oldRecordJSON, newRecordJSON, DateTime.Now);

...Any quick & easy way to implement MySerializer.serialize ?

Thanks!

Answer 1

If you're just wanting some specific properties of your employee, consider creating a basic model and serialising that.

var serializer = new JavaScriptSerializer();
serializer.Serialize(new MyEmployeeModel{ // set fields here});

You can build this as a converter if you wish, that's how I'd do it.

I have an interface, IConverter<TInputType, TOutputType> from which you can create a converter to inject (or whatever you want to do) into your code.

public interface IEmployeeFromDatabaseToBasicEmployeeModelConverter 
     : IConverter<TheDBType, MyEmployeeModel>{}

public class EmployeeFromDatabaseToBasicEmployeeModelConverter :
                               IEmployeeFromDatabaseToBasicEmployeeModelConverter 
{
  public MyEmployeeModel Invoke(TheDBType myDbTypeObject)
  {
     return new MyEmployeeModel{
      // set properties.
     }
  }
}