internal partial class OpenSaveReportWizardForm : Form
{
public event EventHandler saveEvent;
private void saveButton_Click(object sender, EventArgs e)
{
  saveEvent?.Invoke(this, e);
}
}

internal class Database
 {
  public Database()
  {
     using (var wizardForm = new  OpenSaveReportWizardForm(m_Opening,m_ConnectionProperties,m_ColumnProperties))
     {
        wizardForm.saveEvent += (sender, e) => HandleSaveMethod( );
     }
  }

public void HandleSaveMethod()
  {
   // do something
  }