Datagridview value error

Question

For my project i have two forms

FORM2 , STOCKITEMCDA
FORM2 has a custom datagridview with the following method

      public partial class CustomControl1 : DataGridView   

  {
      protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
        {
            const int WM_KEYDOWN = 0x0100;
            const int WM_SYSKEYDOWN = 0x0104;
            int rowIndex = this.CurrentCell.RowIndex;
            int columnIndex = this.CurrentCell.ColumnIndex;

            // Check for the desired shortcut and perform the appropriate action
            if (columnIndex == 0 && (msg.Msg == WM_KEYDOWN || msg.Msg == WM_SYSKEYDOWN) && keyData == (Keys.Alt | Keys.C))
            {
                StockitemCDA messForm = new StockitemCDA();

                Point PositionX = this.PointToScreen(Point.Empty);
                int LeftScreenX = PositionX.X;

                Point PositionY = this.PointToScreen(Point.Empty);
                int TopScreenY = PositionY.Y;

                messForm.StartPosition = FormStartPosition.Manual;
                messForm.Location = new Point(LeftScreenX, TopScreenY);
                messForm.ShowInTaskbar = false;
                messForm.ShowDialog();
                if (messForm.ShowDialog() == DialogResult.Yes)
                {
                    this.Rows[rowIndex].Cells[columnIndex].Value = messForm.textbox1data;
                }      
                
                return true; // return true means the shortcut key has been processed
            }

            // If it is not the desired shortcut key, call the method of the base class for default processing
            return base.ProcessCmdKey(ref msg, keyData);
        }

by using the above code , i am getting the value of textbox1data from the StockitemCDA but Now the problem is when the control returns to the Form2 , I am not getting any value back to the datagridview. Please suggest that what is causing this behaviour .

Answer 1

The following is conceptual which can be plugged into your code with of course modifications.

Here in the child form, in this case we want a value in a TextBox and only close the form if the TextBox has a value.

We setup a delegate/event in the child form.

public delegate void OnPassInformation(string sender);
public event OnPassInformation PassInformation;

Button code

private void SubmitButton_Click(object sender, EventArgs e)
{
    if (!string.IsNullOrWhiteSpace(FirstNameTextBox.Text))
    {
        PassInformation?.Invoke(FirstNameTextBox.Text);
        DialogResult = DialogResult.OK;
    }
    else
    {
        MessageBox.Show("Need a first name");
    }
}

Then

The following is in a button click event, would be done in your current code.

private void DisplayButton_Click(object sender, EventArgs e)
{
    using (ChildForm form = new ChildForm())
    {
        form.PassInformation += delegate(string s)
        {
            Debug.WriteLine(s);
        };
        form.ShowDialog(this);
    }
}

The benefits are, no need to access a form control and should be easy to following in the debugger with breakpoints.