C# refresh DataGridView when updating or inserted on another form

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.

For datagridview in C#, use this code

con.Open();
MySqlDataAdapter MyDA = new MySqlDataAdapter();
string sqlSelectAll = "SELECT * from dailyprice";
MyDA.SelectCommand = new MySqlCommand(sqlSelectAll, con);

DataTable table = new DataTable();
MyDA.Fill(table);

BindingSource bSource = new BindingSource();
bSource.DataSource = table;


dataGridView1.DataSource = bSource;
con.Close();

It works for show new records in the datagridview.

for refresh data gridview in any where you just need this code:

datagridview1.DataSource = "your DataSource";
datagridview1.Refresh();

my datagridview is editonEnter mode . so it refresh only after i leave cell or after i revisit and exit cell twice.

to trigger this iimedately . i unfocus from datagridview . then refocus it.

 this.SelectNextControl(dgv1,true,true,false,true);    
 Application.DoEvents();    //this does magic
 dgv1.Focus();

putting a quick example, should be a sufficient starting point

Code in Form A

public event EventHandler<EventArgs> RowAdded;

private void btnRowAdded_Click(object sender, EventArgs e)
{
     // insert data
     // if successful raise event
     OnRowAddedEvent();
}

private void OnRowAddedEvent()
{
     var listener = RowAdded;
     if (listener != null)
         listener(this, EventArgs.Empty);
}

Code in Form B

private void button1_Click(object sender, EventArgs e)
{
     var frm = new Form2();
     frm.RowAdded += new EventHandler<EventArgs>(frm_RowAdded);
     frm.Show();
}

void frm_RowAdded(object sender, EventArgs e)
{
     // retrieve data again
}

You can even consider creating your own EventArgs class that can contain the newly added data. You can then use this to directly add the data to a new row in DatagridView

I wanted to do the exactly same thing.

  public static bool update = false;
  Timer t = null;
  private void RefreshTable()
  {
     t = new Timer();
     t.Interval = 1000;
     t.Tick += new EventHandler(t_Tick);
     t.Enabled = true;
  }

  void t_Tick(object sender, EventArgs e)
  {
     if (update)
        {
           dataGridView.Rows.Clear();
           dataGridView.Refresh();
           setCustomerDetailsTable();
           update = false;
        }
   }

I am using a static variable in the form that contains the dataGridView and access it from form A. when user insert or update details I set the update variable true so that when the next time timer ticks the table updates and set the update as false. That prevent it from updating everytime timer ticks. The setCustomerDetailsTable() is the function that initialy loads the data on Form_Load in my case. I am sure this is not the best way. However I am using this timer to show the clock on the UI as well. So I assign it this task as well. When I call RefreshTable() on Form_Load it does what I wanted.

Create a small function and use it anywhere

public SqlConnection con = "Your connection string"; 
public void gridviewUpdate()
{
    con.Open();
    string select = "SELECT * from table_name";
    SqlDataAdapter da = new SqlDataAdapter(select, con);
    DataSet ds = new DataSet();
    da.Fill(ds, "table_name");
    datagridview.DataSource = ds;
    datagridview.DataMember = "table_name";
    con.Close();
}