update child class with parent in entity framework

public void Update(UpdateParentModel model)

{

    var existingParent = _dbContext.Parents

        .Where(p => p.Id == model.Id)

        .Include(p => p.Children)

        .SingleOrDefault();


    if (existingParent != null)

    {

        // Update parent

        _dbContext.Entry(existingParent).CurrentValues.SetValues(model);


        // Delete children

        foreach (var existingChild in existingParent.Children.ToList())

        {

            if (!model.Children.Any(c => c.Id == existingChild.Id))

                _dbContext.Children.Remove(existingChild);

        }


        // Update and Insert children

        foreach (var childModel in model.Children)

        {

            var existingChild = existingParent.Children

                .Where(c => c.Id == childModel.Id)

                .SingleOrDefault();


            if (existingChild != null)

                // Update child

                _dbContext.Entry(existingChild).CurrentValues.SetValues(childModel);

            else

            {

                // Insert child

                var newChild = new Child

                {

                    Data = childModel.Data,

                    //...

                };

                existingParent.Children.Add(newChild);

            }

        }


        _dbContext.SaveChanges();

    }

}

 Nguồn:https://www.codegrepper.com/code-examples/csharp/update+child+class+with+parent+in+entity+framework

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