Is any difference in calling function in form_load and button_click?

Question

I have done a window form application by showing the data to the datagridview. But there was some problem when the data showing in the datagridview.

The Function :

private void MySQL_ToDatagridview4()
{
    dataGridView3.Columns.Clear();
    mcon.Close();
    mcon.Open();
    MySqlDataAdapter MyDA = new MySqlDataAdapter();
    string sqlSelectAll = "SELECT Item_Name,Item_Pic from stockitem ORDER BY Main_Category_ID ASC, Item_Name ASC";
    MyDA.SelectCommand = new MySqlCommand(sqlSelectAll, mcon);
    DataTable table = new DataTable();
    MyDA.Fill(table);
    BindingSource bSource = new BindingSource();
    bSource.DataSource = table;
    this.dataGridView3.DataSource = bSource;
    DataGridViewImageColumn imageColumn = new DataGridViewImageColumn();
    imageColumn.HeaderText = "Pic";
    dataGridView3.Columns.Insert(0, imageColumn);
    for (int i = 0; i < table.Rows.Count; i++)
    {
        try
        {
            String pic = table.Rows[i]["Item_Pic"].ToString();
            Byte[] bitmapData = Convert.FromBase64String(FixBase64ForImage(pic));
            System.IO.MemoryStream streamBitmap = new System.IO.MemoryStream(bitmapData);
            def = new Bitmap((Bitmap)Image.FromStream(streamBitmap));
        }
        catch (Exception e)
        {
            MessageBox.Show(e.StackTrace);
        }
        dataGridView3.Rows[i].Cells[0].Value = def;
    }
    dataGridView3.Columns.Remove("Item_Pic");
    foreach (DataGridViewRow row in dataGridView3.Rows)
    {
        row.Height = 110;
    }
    foreach (DataGridViewColumn col in dataGridView3.Columns)
    {
        col.Width = 110;
    }

    for (int i = 0; i < dataGridView3.ColumnCount; i++)
    {
        dataGridView3.Columns[i].SortMode = DataGridViewColumnSortMode.NotSortable;
        dataGridView3.AutoResizeColumns();
        dataGridView3.Columns[i].DefaultCellStyle.Font = new System.Drawing.Font("Verdana", 8F, FontStyle.Bold);
    }
    mcon.Close();
}

Called in Form_Load

private void Form1_Load(object sender, EventArgs e)
{
    MySQL_ToDatagridview4();
}

Result:

Then when I click the button

private void button6_Click(object sender, EventArgs e)
{
    MySQL_ToDatagridview4();
}

Result:

Why the result is so different? It's calling the same function.

Answer 1

yes. there is a difference. Refer Form events life cycle. Form Load event occurs before a form is shown for the first time.

Try using Form shown event. It might help you, make sure UI thread is smooth (I mean to say avoid using Message box kind of stuff until page is fully shown and painted).