Keeping the parent DialogButton open after the child DialogButton is closed

Question

I'm having a problem in keeping the Parent Form to be opened till I close after using ShowDialog() .

I've been trying regarding this but couldn't get. I think there is something simple that I might have been missing. Can you please help me reg this?

The problem is, I have Form 1, on pressing one button, Form 2 opens. I do some validations in Form 2, and check for the validations. If the validation doesn't pass, I open a DialogBox form, with Retry and Cancel. If I press Retry, The control should go back to the Form 2 and form 2 should not close. If the press Cancel, both the DialogBox form and the Form 2 should close. Right now, regardless of what I press, both the forms close.

I have looked online and couldn't find any solution. Went through this solution, but both the forms are still closing for me. Why does closing a nested child dialog also close the parent dialog?

My code:(Sample example scenario)

Form 1:

private void button1_Click(object sender, EventArgs e)
{
    Form2 testForm = new Form2();
    DialogResult dialogResult = new DialogResult();
    dialogResult = testForm.ShowDialog(this);
    if(dialogResult == DialogResult.OK)
    {
        //Do something
    }
}

Form 2:

private void button1_Click(object sender, EventArgs e)
{

    DialogResult validDataResult = MessageBox.Show("Invalid Data Entered. Please provide the correct data."
            , "Data Management"
            , MessageBoxButtons.RetryCancel);

    if (validDataResult == DialogResult.Cancel)
    {
        this.Close();
    }
}

Answer 1

in Form2.cs do your validation and then
(assuming validationOK is the true/false result of your checks)

if(validationOK == false)
{
    // Ask retry or cancel to the user
    if(DialogResult.Cancel == MessageBox.Show("Validation Fail", "Validation failed, press retry to do it againg", MessageBoxButtons.RetryCancel))
        this.DialogResult.Cancel; // Set the dialog result on form2. This will close the form.

    // if you have the validation done in a button_click event and that button has its
    // property DialogResult set to something different than DialogResult.None, we need
    // to block the form2 from closing itself.

    // uncomment this code if the above comment is true
    // else
    //    this.DialogResult = DialogResult.None;
}