C# refresh DataGridView when updating or inserted on another form

Question

I have 2 forms which are form A and form B,

form A allowes user to insert and update student information.

form b is only a DataGridView and button there.

When I insert student on form A, then I go to form B, the new student did not show on the DataGridView , and if I rerun the program, the new student will appear in form B.

I tried using this on button on form b

datagridview1.refresh();
datagridview1.update();

but it's still not working.

---

Edited:

My code for inserting a worker

cmd = new OleDbCommand("insert into FWINFOS (ID,Name,Gender,DateOfBirth,Race,WorkingPlace,PassportNO,DateOfExpire,[Position],Photo) values('" + textBox5.Text + "','" + textBox1.Text + "','" + textBox2.Text + "','" + dateTimePicker1.Value + "','" + textBox3.Text + "','" + textBox4.Text + "','" + textBox6.Text + "','" + dateTimePicker2.Value + "',@Position,@Photo)", con);


        cmd.Parameters.AddWithValue("@Position", comboBox1.SelectedText.ToString());
        conv_photo();

        con.Open();
        int n = cmd.ExecuteNonQuery();
        //cmd.ExecuteNonQuery();
        con.Close();
        if (n > 0)
        {
            MessageBox.Show("Inserted");
            loaddata();

            rno++;
        }
        else
            MessageBox.Show("No Insert");



    }

my Datagridview1(Form2) doesn't automatically update when I inserted a new worker. But if I rerun the application, the new worker appears.

Answer 1

// Form A
public void loaddata()
{
    //do what you do in load data in order to update data in datagrid
}

then on Form B define:

// Form B
FormA obj = (FormA)Application.OpenForms["FormA"];

private void button1_Click(object sender, EventArgs e)
{
    obj.loaddata();
    datagridview1.Update();
    datagridview1.Refresh();
}

Answer 2

DataGridView.Refresh and And DataGridView.Update are methods that are inherited from Control. They have to do with redrawing the control which is why new rows don't appear.

My guess is the data retrieval is on the Form_Load. If you want your Button on Form B to retrieve the latest data from the database then that's what you have to do whatever Form_Load is doing.

A nice way to do that is to separate your data retrieval calls into a separate function and call it from both the From Load and Button Click events.