Vista - Untrapable exception when deleting last row in databound DataGridV

Hi everyone,
Background: I'm working with a standard Windows Forms DataGridView control.
It's databound to a List<> of custom business objects.

When I delete the LAST row using the user delete event (Del key press), I
get an ArgumentOutOfRangeException exception when I delete the last row of
the DataGridView:

Index was out of range. Must be non-negative and less than the size of the
collection.
Parameter name: index

This exception bubbles up to Main(). It has no stack trace and has no
InnerException.

I do NOT get this exception when I delete the last row when the delete is
triggered from a context menu item.


Note, the exception occurs after the UserDeletingRow event, and therefore is
not captured by the try/catch block in the first event handler. Also note
that the exception happens for both grids, but only after the UserDeletingRow
event, not after the context menu event handler event.

Any suggestions on how to track this down better (get a stack trace, trap
the exception, etc.), or any suggestions on how to fix the problem would be
greatly appreciated!

The relevant event handlers and associated methods are below:


private void dataGridViewVocabProperties_UserDeletingRow(object
sender, DataGridViewRowCancelEventArgs e)
{
Vocabulary selectedVocabItem = bindingSourceVocabulary.Current
as Vocabulary;
VocabularyPropertyListItem propertyItem =
dataGridViewVocabProperties.Rows[e.Row.Index].DataBoundItem as
VocabularyPropertyListItem;

try
{
DialogResult result =
DeleteVocabularyProperty(selectedVocabItem,
propertyItem.PropertyName,

String.Format(DELETE_ASSOCIATION_PROPERTY_FORMAT_STRING,
propertyItem.PropertyName, selectedVocabItem.Term),
DELETE_VOCABULARY_PROPERTY_CAPTION);

if (result == DialogResult.No)
{
e.Cancel = true;
}
}
catch (Exception ex)
{
int i = 1;
}
}

private void
dataGridViewAssociationProperties_UserDeletingRow(object sender,
DataGridViewRowCancelEventArgs e)
{
Vocabulary selectedVocabItem = bindingSourceVocabulary.Current
as Vocabulary;
AssociationPropertyListItem propertyItem =
dataGridViewAssociationProperties.Rows[e.Row.Index].DataBoundItem as
AssociationPropertyListItem;

AssociationListItem associationItem =
bindingSourceAssociations.Current as AssociationListItem;

DialogResult result =
DeleteAssociationProperty(selectedVocabItem,
associationItem.AssociationServiceObject.GUID,
propertyItem.PropertyName,
String.Format(DELETE_ASSOCIATION_PROPERTY_FORMAT_STRING,
propertyItem.PropertyName, selectedVocabItem.Term),
DELETE_VOCABULARY_PROPERTY_CAPTION);

if (result == DialogResult.No)
{
e.Cancel = true;
}
}

private DialogResult DeleteVocabularyProperty(Vocabulary
selectedVocabItem, string propertyName, string promptMessage, string
promptCaption)
{
DialogResult result = MessageBox.Show(promptMessage,
promptCaption, MessageBoxButtons.YesNo, MessageBoxIcon.Question);

if (result == DialogResult.Yes)
{
Vocabulary currentObj =
GetCompleteVocabFromLocalCacheOrLoadFromService(selectedVocabItem.GUID);

try
{

Q6.ProblemDomain.Q6ServicesDAO.DeleteVocabularyProperty(currentObj.GUID,
propertyName);
Vocabulary updatedVocab =
GetCompleteVocabFromServiceAndUpdateLocalCache(currentObj.GUID);

RefreshVocabularyPropertiesBindingSource(updatedVocab);
SetBindingSourcesForSelectedVocabulary();

MessageBox.Show(
String.Format("The vocabulary property for the
[{0}] vocabulary item was successfully deleted.", updatedVocab.Term) +
Environment.NewLine + String.Format("GUID: {0}",
updatedVocab.GUID),
"Success");
}
catch (Exception ex)
{
MessageBox.Show("An error has occurred: " + ex.Message,
"Exception");
}
finally
{
this.Cursor = Cursors.Default;
}
}

return result;
}

private DialogResult DeleteAssociationProperty(Vocabulary
selectedVocabItem, string associationGUID,
string propertyName, string promptMessage, string promptCaption)
{
DialogResult result = MessageBox.Show(promptMessage,
promptCaption, MessageBoxButtons.YesNo, MessageBoxIcon.Question);

if (result == DialogResult.Yes)
{
Vocabulary currentObj =
GetCompleteVocabFromLocalCacheOrLoadFromService(selectedVocabItem.GUID);

try
{

Q6.ProblemDomain.Q6ServicesDAO.DeleteAssociationProperty(associationGUID,
propertyName);
Vocabulary updatedVocab =
GetCompleteVocabFromServiceAndUpdateLocalCache(currentObj.GUID);

RefreshAssociationsBindingSource(updatedVocab);

MessageBox.Show("The association property for the
selected association was successfully deleted." +
Environment.NewLine + String.Format("GUID: {0}",
associationGUID),
"Success");
}
catch (Exception ex)
{
MessageBox.Show("An error has occurred: " + ex.Message,
"Exception");
}
finally
{
this.Cursor = Cursors.Default;
}
}

return result;
}


private void deletePropertyToolStripMenuItem_Click(object sender,
EventArgs e)
{
ToolStripMenuItem item = sender as ToolStripMenuItem;
ContextMenuStrip menu = item.Owner as ContextMenuStrip;
DataGridView grid = menu.SourceControl as DataGridView;

Vocabulary selectedVocabItem = bindingSourceVocabulary.Current
as Vocabulary;

string promptMessage;
string promptCaption;

if (grid.Name == dataGridViewVocabProperties.Name)
{
VocabularyPropertyListItem propertyItem =
dataGridViewVocabProperties.Rows[lastPropertyGridRowIndex].DataBoundItem as
VocabularyPropertyListItem;
promptMessage =
String.Format(DELETE_VOCABULARY_PROPERTY_FORMAT_STRING,
propertyItem.PropertyName, selectedVocabItem.Term);
promptCaption = DELETE_VOCABULARY_PROPERTY_CAPTION;
DeleteVocabularyProperty(selectedVocabItem,
propertyItem.PropertyName, promptMessage, promptCaption);
}
else if (grid.Name == dataGridViewAssociationProperties.Name)
{
AssociationPropertyListItem propertyItem =
dataGridViewAssociationProperties.Rows[lastPropertyGridRowIndex].DataBoundItem as AssociationPropertyListItem;
promptMessage =
String.Format(DELETE_ASSOCIATION_PROPERTY_FORMAT_STRING,
propertyItem.PropertyName);
promptCaption = DELETE_ASSOCIATION_PROPERTY_CAPTION;

AssociationListItem associationItem =
bindingSourceAssociations.Current as AssociationListItem;
DeleteAssociationProperty(selectedVocabItem,
associationItem.AssociationServiceObject.GUID, propertyItem.PropertyName,
promptMessage, promptCaption);
}
else
{
throw new Exception("Invalid sender encountered: " +
sender.ToString());
}

}

private void SetBindingSourcesForSelectedVocabulary()
{
Vocabulary selectedVocab = bindingSourceVocabulary.Current as
Vocabulary;
Vocabulary completeVocab =
GetCompleteVocabFromLocalCacheOrLoadFromService(selectedVocab.GUID);

SetBindingSourcesForGivenVocabulary(completeVocab);
}
private void RefreshVocabularyPropertiesBindingSource(Vocabulary
vocab)
{
bindingSourceVocabularyProperties.DataSource =
new
SortableBindingList<VocabularyPropertyListItem>(VocabularyPropertyListItem.GetVocabularyPropertyListItem(vocab.Properties));
}
private void RefreshAssociationsBindingSource(Vocabulary vocab)
{
bindingSourceAssociations.DataSource =
new
SortableBindingList<AssociationListItem>(AssociationListItem.GetAssociationListItemList(vocab.Associations));
}
private void SetBindingSourcesForGivenVocabulary(Vocabulary vocab)
{
txtUpdateVocabTerm.Text = vocab.Term;
lblUpdateVocabGUIDValue.Text = vocab.GUID;

bindingSourceAssociations.DataSource =
new
SortableBindingList<AssociationListItem>(AssociationListItem.GetAssociationListItemList(vocab.Associations));

RefreshVocabularyPropertiesBindingSource(vocab);

SetAssociationPropertiesBindingSource();

ClearFactTable();
}