不通过实体框架模型C＃将数据添加到SQL数据库

Question

This question might be asked but I could not find the answer for now so please help me with this. I'm trying to add a new row into my SQL database through EF model. Is there anything wrong because it looks okay but actually does not insert anything to the table.

private void Bsubmit_Click(object sender, EventArgs e)
{
        using(var db = new Models.CompanyDBEntities())
        {
            db.Clients.Add(new Client
            {
                name = nameTB.Text,
                age = Convert.ToInt32(ageTB.Text)
            });
            db.SaveChanges();
        }
}

EDIT** So now I'm adding a Change Tracker to see what's going on:

        if (db.ChangeTracker.HasChanges()){
            db.SaveChanges();
            var clients = (from c in db.Clients select c).ToList();
            string updated = "";
            foreach (var c in clients)
            {
                updated += c.Name;
            }
            MessageBox.Show(updated);
        }

The message box does show up the name of current clients in the data together with the name I just added. I think the problem here is .SaveChanges() it's not working. I did not find the solution yet.

Answer 1

Try add Parameterless Constructor to your class and try again, just guess:

public class Client
{
    public Client()
    {

    }

    public string name ...
    public int age ...
    ...
}

and use parentheses when new: 'new Client () {'

        db.Clients.Add(new Client()
        {
            name = nameTB.Text,
            age = Convert.ToInt32(ageTB.Text)
        });

Answer 2

尝试运行Sql Server Profiler ，并检查针对您的语句执行的查询，很可能您会找到答案。