title: How to insert, update and delete records of a DataGridView to DataBase via BindingNavigator
body: <p>I have a <code>Student</code> table and a bunch of other tables in my database called <code>University</code> and I used Entity Framework to connect to it in my winforms application.
  <img src="https://i.stack.imgur.com/ZLCzG.jpg" alt="My Entity Framework model"></p>
  
  <p>I created a <code>DataSource</code> from the <code>Student</code> table inside my Entity Framework model.
  <img src="https://i.stack.imgur.com/ovWhJ.jpg" alt="My Data Source"></p>
  
  <p>then I dragged the <code>DataSource</code> on to my form.(See the pic below)<br>
  I know how to populate the records of the <code>student</code> table (here is just one record in my DB) into the <code>DataGridView</code>, with no problem using this piece of code:</p>
  
  <pre><code>//An instance of my EFModel
      Oublic UniversityEntities UE = new UniversityEntities();
   private void Form1_Load_1(object sender, EventArgs e)
      {
          studentBindingSource.DataSource = UE.Students.ToList();
      }
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/qiPxA.jpg" alt="My Form"></p>
  
  <p>But I want to use <code>BindingNavigator</code> to insert/update/delete records from/to the database and I don't khow how it's possible, considering that I use Entity Framework.</p>
  
  <p>For example,I tried this to save changes after editing a row, but it didn't work:</p>
  
  <pre><code> private void studentBindingNavigatorSaveItem_Click(object sender, EventArgs e)
      {
          UE.SaveChanges();
      }
  </code></pre>